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Physics set 2

Q1. The unit of power is- 
power unit is 
(a) Hertz / Hertz 
(b) Volts / Volt 
(c) Watt / Watt 
(d) Neutrons / neutron
Show Answer
Ans.(c)
Sol. In the field of Physics watt is measurement of power, describing the rate at which electricity is being used at a specific moment.
Power = Work/Time
The S.I. unit of power is watt, which is equal to joule per second.

Q2. The unit of the force is- 
What is the unit of force- 
(a) Faraday / Faraday 
(b) Fermi / Fermi 
(c) Newton / Newton 
(d) Rutherford / Rutherford
Show Answer
Ans.(c)
Sol. The S.I. unit of Force is ‘Newton’ or Kg. m/sec2.
Force = mass × acceleration
The net force on an object is product of object mass and acceleration generated.

Q3 The unit of work is: 
What is the unit of work  :
(a) Joule / Joule 
(b) Neutron / Neutron 
(c) Watt / watt 
(d) Dyne / witch
Show Answer
Ans.(a)
Sol. When a force acts to move an object, then work done by the force is equivalent to the product of force and displacement in the direction of force. It is a scalar quantity. The S.I unit of work is Newton metre, which is also called as Joule. Joule is also the unit of Energy.

Q4. The SI unit of electrical resistivity of conductor  is- 
SI unit of electrical resistance of the conductor is
(a) Faraday / Faraday 
(b) Volts / Volt 
(c) Ampere / Ampere 
(d) Ohm-metre (Ω⋅m ). / Ohm meter (Ω⋅m)
Show Answer
Ans.(d)
Sol. The SI unit of electrical resistivity is the ohm-metre (Ω-m).

Q5. Light year is the unit of-  
light year whose unit is
(a) Distance / Distance 
(b) Time / time 
(c) Speed ​​of light / speed 
of light (d) Intensity of light / Light intensity
Show Answer
Ans.(a)
Sol. Light year is a unit of astronomical distance equivalent to the distance that light travels in one year, which is 9.46 × 1015 metres.

Q6. A parsec is a unit of distance to measure the distance pertaining to the stars in the sky, which is equal   
to -
(a ) 4.25 light-years / light year 
(b) 3.26 light-years / light year 
(c) 4.50 light-years / light year 
(d) 3.05 light-years / light year
Show Answer
Ans.(b)
Sol. A PARSEC is a unit of length used to measure the astronomically large distance of objects outside the solar system.
1 PARSEC = 3x 1016 Metres
1 Light year = 9.46 x 1015 Metres
So, 1 PARSEC = 3.262 light years.

Q7 PARSEC is the unit of:  
PARSEC whose unit is
(a) Distance / Distance 
(b) Time / time 
(c) Light intensity / intensity of light 
(d) Magnetic force / magnetic force
Show Answer
Ans.(a)
Sol. A PARSEC is a unit of length used to measure the astronomically large distance of objects outside the solar system.
One parsec is equal to about 3.26 light-years (30 trillion km or 19 trillion miles) in length. 

Q8. Which unit of measurement is multiplied by 0.39 to convert it to 'inches'? 
Which measurement unit is multiplied by 0.3 inches to convert to 'inch'? 
(a) Millimetre / millimeter 
(b) Centimetre / centimeter 
(c) Metre / meter 
(d) Decimetre / decimeter
Show Answer
Ans.(b)
Sol. 1 Centimetre = 0.39 inch, so we can multiply centimeter by 0.39 to convert it to inches’.

Q9. How can the height of a person who is six feet tall, be express (approx) in nanometer? 
In the form of a height of six feet tall person, in the nanometer (approx) in which form can be expressed? 
(a) 183 × 10 ^ 6nm 
(b) 234 × 10 ^ 6nm 
(c) 183 × 10 ^ 7nm 
(d) 181 × 10 ^ 7nm
Show Answer
Ans. (C) 
Sol. 1 nonaometer = 10-9 meters 
1 Feet = 0.305 meters 
1 Feet = 30.5 107 nanometers 
6 Feet = 6 30.5 107 nanometers 
= 183 107 nanometers

Q10. A nanometer is equal to- A nanometer is equal to  
-
(a) 10 ^ (-6) cm 
(b) 10 ^ (-7) cm 
(c) 10 ^ (-8) cm 
(d) 10 ^ (-9 ) cm
Show Answer
Ans.(b)
Sol. A nanometer is equal to- 10-7) cm

Q11. Ampere is the unit of  
ampere whose unit is
(a) Voltage / electric pressure 
(b) Electric current / electric current 
(c) Resistance / resistance 
(d) Power / power
Show Answer
Ans.(b)
Sol. Ampere is a unit to measure electric current. If one Ampere current is flowing in any conducting wire, it means 6.25 × 10-18 electrons are entering per second from one direction and same amount of electrons flows from the other end per second.

Q12. Megawatt is the 
measurement unit of power which is- Megawatt is the measurement unit of power that- 
(a) is generated / 
b (Consumed / consumed 
) (c) Saved / saved 
(d) Lost In transmission / transmission losses
Show Answer
Ans.(a)
Sol. Megawatt is the measuring unit of power, which is generated in electricity generation plants. 1 Megawatt is equal to 106 (million) watt.

Q13. Match List-1 with List-II and select the correct answer from the code given below: 
List-I List-II
(Physical quantities) (Units)
A. Acceleration 1. Joule 
B. Force  2. Newton second 
C. Work done 3. Newton 
D. Impulse  4. Metre/second2
Code: ABCD
(a) 1 234
(b) 3412
(c) 2 341

(d) 4312
Show Answer
Ans.(d)
Sol. Acceleration is the rate of change of velocity of an object. The S.I. unit of acceleration is the metre per second square (m/s2). The S.I. unit of force is Newton (N). The S.I. unit of Impulse is the Newton Second (N.S). The S.I. unit of Work is Joule.

Q14. Match List-I with List-II and select the correct answer using codes given below: 
List-I List-II
(Units) (Parametric quantities)
A. Watt 1. Heat  
B. Knot  2. Navigation 
C. Nautical mile 3. Speed of a ship 
D. Calorie  4. Power 
Code:  ABCD
(a) 3 142
(b) 1234
(c) 4 321
(d) 2413
Show Answer
Ans.(c)
Sol. The SI unit of power is the Watt (w), which is equal to one joule per second. Knot is the unit of measuring of speed of a ship. Nautical mile is a unit of distance used by navigators in sea. Calorie is a unit of measuring heat and energy.
Q15. How many waves are there in a horsepower? 
How many watts are there in a horsepower? 
(a) 1000 
(b) 750 
(c) 746 
(d) 748
Show Answer
Ans.(c)
Sol. Horse power is a unit of measurement of power (the rate at which work is done).
1 Watt = 1 Joule/second
1 Horse power = 746 watt.



Q1. Match List-I (Quantity) with List-II (Units) and select the correct answer using the codes given below the lists:  
Match the list-I (quantity) with the list-II (unit) and enter the code below the lists Select the correct answer using. 
List I / List I  List II / List II 
A. High Speed ​​/ Fast Speed  1. Mach 
/ Mac B. Wavelength / Wavelength  2. Angstrom / Angstrom 
C. Pressure / Pressure  3. Pascal / Pascal 
D. Energy / Energy  4. Joule / Joule 
ABCD 
(a) 2  134 
(b) 1243 
(c) 1  234 
(d) 2143
Show Answer
Ans.(c)
Sol. In fluid mechanics, the Mach number is a dimensionless quantity representing the ratio of the speed of a body to the speed of sound in the surrounding medium. Objects moving at speed higher than Mach 1 travelling at Supersonic speed. So Mach is used to represent the high speed. Wavelength is measurement in Angstrom while pressure is measured in Pascal and energy in Joule.

Q2. 'Joule' is related to energy in the same way as 'Pascal' is related to: 'Joule' is related to energy in the same way as 'Pascal' is related to  
___
(a) mass / mass 
(b) pressure / pressure 
( c) Density / Density 
(d) Purity / Purity
Show Answer
Ans.(b)
Sol. In fluid mechanics, the Mach number is a dimensionless quantity representing the ratio of the speed of a body to the speed of sound in the surrounding medium. Objects moving at speed higher than Mach 1 travelling at Supersonic speed. So Mach is used to represent the high speed. Wavelength is measurement in Angstrom while pressure is measured in Pascal and energy in Joule.

Q3 One micron is equal to- 
one micron is equal to- 
(a) 1/10 mm / mm 
(b) 1/100 mm / mm 
(c) 1/1000 mm / mm 
(d) 1 / 10,000 mm / mm
Show Answer
Ans.(c)
Sol. 1 micron = 〖10〗^(–6) m.
=〖10〗^(–6)×〖10〗^3 mm.
= 1/〖10〗^3  mm.
= 1/1000 mm.

Q4. One micron represents a length of- 
length of  a micron -
(a) 10 ^ (-6) cm / cm 
(b) 10 ^ (-4) cm / cm 
(c) 1 mm / cm 
(d) 1 m / cm
Show Answer
Ans.(b)
Sol. One micron represents a length of 〖10〗^(–6) m. It is represented by μ sign.
1 micron = 0.000001 m. = 0.0001 cm.
=1/10000  cm.=1/〖10〗^4  cm.=〖10〗^(-4) cm. 

Q5. Which one is the correct match? 
Which of the following is not a perfect match? 
(a) Decibel / dB  Unit Of Sound Intensity / Sound intensity unit 
(b) Horsepower /  hp  Unit Of Power / power unit 
(c) Nautical miles / nautical mile  Unit Of Naval Distance / Naval distance unit 
( d) Celsius / Celsius  unit of heat / heat unit
Show Answer
Ans.(d)
Sol. Celsius is a scale and unit of measurement for temperature. Heat is measured in Calories. Nautical mile is used to measure distance at sea. 1 nautical mile is equal to 1.852 km. The S.I unit of power is Watt (w), which is equal to Joule per second. Another unit of power includes horsepower (hp) or metric horsepower. 1 horsepower is equal to 746 watts. Decibel is used to measure the sound intensity.

Q6. Which one is the unit of heat? 
Which of the following is not a unit of heat
(a) Calorie / calorie 
(b) Kilocalorie / kilocalories 
(c) Kilojoule / kJ 
(d) Watt / Watt
Show Answer
Ans.(d)
Sol. The watt is a derived unit of power in the International System of Units (SI). Rest of all are the units of heat.

Q7 A distance of 1 km means-  
1 km distance means-
(a) 100m / M 
(b) 1000 cm / Cm 
(c) 1000m / M 
(d) 100 cm / Cm
Show Answer
Ans.(c)
Sol. The SI base unit for distance is metre. 1 Km. is equal to 1000m. 1 m is equal to 100 cm. 

Q8. One pikogram is equal to- 
pikogram is equal to- 
(a) 10 ^ ( -6 ) gram / gram 
(b) 10 ^ ( -9 ) gram / gram 
(c) 10 ^ (-12) gram / gram 
(d) ) 10 ^ (- 15) gram / gram
Show Answer
Ans.(c)
Sol. The smaller units of measuring mass are Milligram, Microgram, Pikogram and Femtogram.\
1 Pikogram = 〖10〗^(-12) gram  1 Milligram = 〖10〗^(-3) gram
1 Microgram = 〖10〗^(-6) gram 1 Nanogram = 〖10〗^(-9) gram
1 Femtogram = 〖10〗^(-15) gram

Q9. Candela is a unit of measuring: 
Kendella is a unit of  measure
(a) Humidity / humidity 
(b) Luminous intensity / light intensity 
(c) Rainfall / rainfall 
(d) Temperature / Temperature
Show Answer
Ans.(b)
Sol. The candela is the Standard International (SI) unit of luminous Intensity.

Q10. What is the unit of atmospheric pressure? 
What is the unit of atmospheric pressure? 
(a) Bar / Bar 
(b) Knot / Knot 
(c) Joule / Joule 
(d) Ohm / Om
Show Answer
Ans.(a)
Sol. Bar is metric (but not SI) unit of pressure. It is equal to 105 newton/metre2. Pascal is SI unit of pressure.
Or 1 bar = 105 Pascal. 

Q11. 1 kg / cm2 pressure is equal to:  
1 kg / square cm is equal to:
(a) 0.1 bar / bar 
(b) 1.0 bar / bar 
(c) 10.0 bar / bar 
(d) 100.0 bar / bar
Show Answer
Ans.(b)
Sol. 1 Dyne = 1.02 × 10^(-6) Kg.
And 1 Bar = 10^6 dyne/cm2
Therefore substituting the value of Dyne into the value of Bar-
1 Bar = 10^6 dyne/cm2 = 1.02 × 10^(-6)×10^6  Kg/cm^2
=1.02 Kg/cm^2

Q12. 1 barrel of oil is equal to  
1 barrel oil is equal to the following
(a) 131 liters / liter 
(b) 159 liters / liter 
(c) 179 liters / liter 
(d) 201 liters / liter
Show Answer
Ans.(b)
Sol. Previously the amount of oil was measured in barrels but now, it is measured in cubic metres.
1 barrel = 158.9873 litre
1 barrel = 0.158987 cubic metre
1 barrel = 42 U.S. gallon
1 barrel = 34.9723 U.K. gallons.

Q13. The smallest unit of length is-  
the smallest unit of length is
(a) Micron / micron 
(b) Nanometre / nanometer 
(c) Angstrom / angstrom 
(d) Fermimetre / Frmimitr
Show Answer
Ans.(d)
Sol. 1 Micron = 10^(–6) metre
1 Nanometre = 10^(-9) metre
1 Angstrom = 10^(-10) metre
1 Fermimetre = 10^(-15) metre
Thus, the smallest unit of length in the given options is fermi metre.

Q14. Match List-I with List-II and select the correct answer using the codes given below the lists. 
Match List-I with List II and select the correct answer using the code given below the list. 
List -I /  list -II / 
Ak Cusec / cusecs  1. Pressure / Pressure 
B. Byte / byte  2. Intensity of Intensity of Earthquake / Earthquake 
C. Richter / Richter  3. Rate of flow / flow rate 
D. Bar / Bar  4. Computer / Computer 
Code / Code: 
D
(a) 1  234 
(b) 3421 
(c) 4  321 
(d) 3412
Show Answer
Ans.(b)
Sol. Cusec is a measure of flow rate and is informal shorthand for “cubic feet per second” (28.317 litres per second). Byte is a unit of digital information in computing and communications that consists of eight bits. The Richter magnitude scale (also Richter scale) assigns a magnitude number to quantify the energy released by an earthquake. The bar is a metric (but not SI) unit of pressure exactly equal to 100,000 Pa.

Q15. What is measured in cusecs? 
What is measured in cusec? 
(a) Purity of water / Water purity 
(b) Depth of water / Depth of water 
(c) Flow of water / Water flow 
(d) Quantity of water / Water quantity
Show Answer
Ans.(c)
Sol. Cusec (Cubic feet per second) is a unit of measuring the flow of water.


Q1. When light passes from one medium to another medium, 
when the light passes through one medium, what does not change  from the following:
(a) Intensity / depth 
(b) Velocity / Speed 
(c) Wavelength / wavelength 
(d) Frequency / Frequency
Show Answer
Ans. (D) 
Sol. When light passes from air to glass or one medium to another, then the frequency of the light remains constant but wavelength and velocity are changed.

Q2. The visible range of solar radiation is- 
The visual limit of solar radiation  is
(a) 100-400 nm 
(b) 400-700 nm 
(c) 740-10000 nm 
(d) None of the above / None of the above
Show Answer
Ans. (B) 
Sol. The electromagnetic spectrum encompasses all type of radiations. The part of the spectrum that reaches earth from the sun is between 100 nm to 10 ^ 6 nm. This band is broken into three ranges - Infrared (above 700 nm), Visible (400 to 700 nm), Ultraviolet (below 400 nm).

Q3 Total internal reflection can take place when light travels from:  
Total internal reflection comes in effect when light passes in ___. 
(a) Diamond to glass / Glass with diamond 
(b) Water to glass / Glass with water 
(c) Air to water / Water by air 
(d) Air to glass / Glass by air
Show Answer
Ans. (A) 
Sol. Total internal reflection takes place when a ray of light is travelling from denser to thinner medium and angle of incidence is greater than critical angle, the ray is completely reflected from surface and meet one another as if the surface is a mirror. So according to options, the situation of option (a) is correct where total internal reflection takes place, it is because diamond is denser than glass

Q4. Human eye is most sensitive to visible light of wavelength  
:
(a) 605nm 
(b) 555nm 
(c) 450nm 
(d) 750nm
Show Answer
Ans. (B) Sol. Under daylight conditions, the average normal sighted human eye is most sensitive at a wavelength of 555 nm.

Q5. The nature of radiation of light is- 
is the nature of the radiation of light 
(a) Like wave / Trngiy 
(b) Like particle / particulate 
(c) Like both of wave and particle / Trngiy and particulate both 
(d) Like neither of wave nor of particle / nor waveable
Show Answer
Ans. (C) 
Sol. The light has a dual nature, sometimes it behaves only as wave and sometimes as light. In the later part of the 19th century and in the beginning of the 20th century, it was realized that black body radiation and the photelectric effect can only be based on particle model of light. Some experiments require light to be a wave, while others require light to be a particle. This led to the acceptance

Q6. Light appears to 
flow in a straight line because - 
(a) It consists of small particles. / Contains small particles 
(b) The velocity of light is very large. / The speed 
of light is very high (c) The wavelength of light is very small. Wavelength of light is very low 
(d) Light is reflected by the surroundings. / Reflected by light environment
Show Answer
Ans. (C) 
Sol. Due to its very small wavelength, the light appears in a straight line.

Q7 Which is the following statement is true? 
Which of the following statements is true? 
(a) The light has a greater velocity / Speed ​​of light is high 
(b) the sound has great velocity / The speed of sound is the highest 
(c) Celestial objects have the greatest velocity / Celestial objects have the highest speed 
(d) Rocket has the greatest velocity. / Rocket speed is the highest
Show Answer
Ans. (A) 
Sol. The speed of light in a vacuum is 3.00 x 10 ^ 8 m / s, while the speed of sound in vacuum is zero and in air is 343 m / s. The speed of light in glass is 2,0 × 10 ^ 8 m / s. The velocity of light The velocity of celestial objects and the rockets in the velocity of light

Q8. The speed of light in the speed of light is velocity is  
approximately -
(a) 3 × 10 ^ 10 meters / sec / m / sec 
(b) 3 × 10 ^ 8 meters / sec / m / sec 
(c) 3 × 10 ^ 8 km / sec / km / second 
(d) 3 × 10 ^ 8 light years / light year
Show Answer
Ans. (B) 
Sol. The speed of light in a vacuum is 3.00 x 10 ^ 8 m / s, while the speed of sound in vacuum is zero and in air is 343 m / s. The speed of light in glass is 2,0 × 10 ^ 8 m / s. The velocity of light The velocity of celestial objects and the rockets in the velocity of light

Q9. Which one of the following phenomena is used in optical fibers? 
Which of the following facts is used in optical fiber? 
(a) Interference / interference 
(b) Refraction / refraction 
(c) Total internal reflection / total internal reflection 
(d) Polarisation / Polarization
Show Answer
Ans. (C) 
Sol. The optical fiber is a very thin strand of glass or plastic cable for transmitting light from one point to another. They work on There is no loss of signal through an optical fiber

Q10. Velocity of light is maximum in- 
The speed of light is maximum  -
(a) Diamond / Diamond 
(b) Water / Water 
(c) Vacuum / Dry 
(d) Hydrogen / Hydrogen
Show Answer
Ans. (C) 
Sol. The speed of light in vacuum is maximum (c = 3 × 10 ^ 8 ms ^ (- 1)). The speed of light decreases gradually in optically denser mediums like water or glass. It is rare in diamond

Q11. The speed of light will be 
minimal during going through- 
(a) Glass / Glass 
(b) Vacuum / Dry 
(c) Water / Water 
(d) Air / Wind
Show Answer
Ans. (A) 
Sol. Any of the object or material that has the maximum speed The glass has the best refractive index among other like, vacuum, water and air.

Q12. Waves used for telecommunication are- 
The waves used for telecommunications  are
(a) Visible light / visible light 
(b) Infrared / infrared 
(c) Ultraviolet / ultraviolet 
(d) Microwave / Micro tangro
Show Answer
Ans. (D) 
Sol. The microwaves are high-frequency signals in the 300 MHz to 300 GHz range. The signals can carry thousands of channels at the same time, making it a very versatile communication system. Microwave ovens Today, microwave is employed by telecommunication industry in the form of both terrestrial relays and satellite communication.

Q13. Earth in about: 
How long does the light from the sun reach the Earth  -
(a) 2 minutes / minute 
(b) 4 minutes / minute 
(c) 8 minutes / minute 
(d) 16 minutes / minute
Show Answer
Ans. (C) 
Sol. The sunlight takes about 500 second or (8 minutes & 20 seconds )to reach the earth.

Q14. When light waves go from air to glass 
then which variables are affected - 
(a) Wavelength, frequency and velocity / wavelength, frequency and velocity 
(b) Velocity and frequency / Velocity and frequency 
(c) Wavelength and frequency / wavelength and frequency 
(d) Wavelength and velocity / wavelength and velocity
Show Answer
Ans. (D) 
Sol. When light passes from air to glass or one medium to another, then the frequency of the light remains constant but wavelength and velocity are changed.

Q15. Which one of the following energy conversion takes place in the process of photosynthesis? 
Which of the following energy conversion is done to complete the process of photosynthesis? 
(a) Light to chemical energy / Chemical energy from light 
(b) Light to thermal energy / thermal energy from light 
(c) Thermal to biochemical energy / thermal to thermal biochemical energy 
(d) Heat to kinetic energy / heat kinetic energy
Show Answer
Ans. (A) 
Sol. Photosynthesis is the process of light energy in chemical energy. Photosynthesis can be represented by the following chemical equation. 
6CO₂ + 6H₂O □ (Chlorophyll) ---> C₆H₁₂O₆ + 6O₂   
Where CO₂ = Carbon dioxide  
H₂O = Water  
C₆H₁₂O₆ = Glucose  
O₆ = Oxygen 

Q1. Long radio waves are reflected by which of the following 
layers of the Earth's surface- Which of the following layers of long wave radios are visible on Earth's surface? 
(a) Troposphere / Troposphere 
(b) Ionosphere / ionosphere 
(c) Tropopause / Tropopoze 
(d) Stratosphere / Stratosphere

Show Answer
Ans. (B) 
Sol. The ionosphere is a region of earth's upper atmosphere from about 65 km. to 400 km altitude It is ionized by solar radiation. It has practical significance, it is influenced by radio propagation to distant places on earth.

Q2. What is reflected by the 
wireless communication back to the surface of the Earth? 
(a) Troposphere / Troposphere 
(b) Stratosphere / stratosphere 
(c) Ionosphere / ionosphere 
(d) Exosphere / Exosphere
Show Answer
Ans. (C) 
Sol. The ionosphere is a region of earth's upper atmosphere from about 65 km. to 400 km altitude It is ionized by solar radiation. It has practical significance, it is influenced by radio propagation to distant places on earth.

Q3 The rise of temperature, the speed of sound in a gas? 
As temperature increases, what changes in the speed of sound in the gas? 
(a) increase / increase 
(b) decreases / decreases 
(c) remains remains the same / 
(d) None of these
Show Answer
Ans. (A) 
Sol. Molecules at high temperatures have more energy, thus they can vibrate faster Since the molecules vibrate faster, sound waves can travel faster The speed of sound in room temperature is 346 meters per second.

Q4. Which waves can not be transmitted through vaccum? 
Which waves can not be transmitted through vacuum? 
(a) Light / Light 
(b) Heat / Heat 
(c) Sound / Sound 
(d) Electromagnetic / Electromagnetic
Show Answer
Ans. (C) 
Sol. Sound waves can not be transmitted through vacuum. It's transmitted through the movement of the sound wave. More generally, sound is a mechanical disturbance which is dependent on a medium to travel. It can be transmitted through solids, liquids, and gases.

Q5. Cosmic rays - 
Cosmic rays 
(a) Are charged particles / charged particles 
(b) Are uncharged particles / discharged particles 
(c) Can be charged as well as uncharged / charged and can also be discharged. 
(d) None of the above / None of the above
Show Answer
Ans. (A) 
Sol. Cosmic rays are not part of electromagnetic spectrum. They are immensely high-energy radiation waves, mainly originating outside the solar system.

Q6. Which one of the following statements is not true about cosmic rays? 
Which of the following statements about cosmic rays is not true? 
(a) They are electromagnetic waves / They are electromagnetic waves 
(b) They have very short wavelength / They have very low wavelength 
(c) They are highly energetic charge particles / They are made from highly energetic charged particles. 
(d) They originate from the sum / They are generated by yoga
Show Answer
Ans. (A) 
Sol. Cosmic rays are not part of electromagnetic spectrum. They are immensely high-energy radiation waves, mainly originating outside the solar system.

Q7 What is the distance between two successive crests or successive troughs called? 
What is the distance between two consecutive top or continuous troughs? 
(a) Amplitude / Dimension 
(b) Wavelength / Wavelength 
(c) Frequency / Frequency 
(d) None of these / None of these
Show Answer
Ans. (B) 
Sol. Wavelength means the distance measured in the direction of a wave from any given point to the next point in the same phase, as from crest to crest. The distance between two successive crests or two successive troughs is the transit wave.

Q8. Which one of the following is used for determining the structure of crystal: 
to determine the structure of crystals is what was used in the following:
(A) Gamma Rays / gamma rays 
(b) X-rays / X-ray 
( c) UV rays / UV rays 
(d) visible light / visible light
Show Answer
Ans. (B) 
Sol. Crystallography is the science that examines crystals which can be found everywhere in nature, from salt to snowflakes to gemstones. Crystallographers use the properties of the crystals to determine the arrangement of atoms and generates knowledge which is used by chemist, physicists and other. Crystallographers use X-rays, neutron, and electron diffraction techniques.

Q9. A radar that detects the presence of an enemy aircraft: 
A radar that detects the presence of enemy aircraft :
(a) Light waves / light waves 
(b) Radio waves / radio waves 
(c) Sound waves / sound waves 
( d) Ultrasound waves / ultrasound waves
Show Answer
Ans. (B) 
Sol. Radar is an object-detection system which uses radio waves to determine the range, angle or velocity of objects. It is used to detect the location of aircraft, ships, spacecraft, motor vehicle etc.

Q10.When there is depletion of ozone in the stratosphere, the wavelength of radiation strikes the earth's surface 
when the ozone depletion in the stratosphere is, what is the wavelength of the radiation  that attacks the surface of the earth? 
(a) 10-10 m / 10-10 m 
(b) 10-7 m / 10-7 m 
(c) 10-2 m / 10-2 m 
(d) 100 m / 100 m
Show Answer
Ans. (B) 
Sol. Ultraviolet radiations are mainly divided into three groups: - UV-A radiations: the long wave UV-A radiations having the wavelength of 320-400 nm. They are the earth of the sun 
UV-B radiations: the medium wave UV-B radiation has the wavelength of 280-320 nm. It is mostly absorbed by the ozone layer. 
UV-C radiations - it has a wavelength of 100-280 nm. It is completely absorbed by ozone layer and atmosphere. 
Therefore, on depletion of ozone in the stratosphere, the wavelength of radiation striking the surface of the earth shall be 100 nm. 
1 nm = 1.0 × 10 ^ ( 
-9 ) m  100 nm = 100 × 10 ^ (-9) 
= 10 ^ 2 × 10 ^ (-9) 
= 10 ^ (-7) m 

Q11. Which one of the following types of waves were used in a night vision tool? 
Which of the following waves is used in the night vision machine? 
(a) Radio waves / radio waves 
(b) Microwaves / microwave 
(c) Infra-red waves / infra-red waves 
(d) None of these / None of these
Show Answer
Ans. (C) 
Sol. Infrared waves are the type of electromagnetic radiations with longer wavelengths. Vision This is done by the target of the target, intruders and hidden bombs. 

Q12. Decibel is a - 
What is decibel? 
(a) musical note / music note 
(b) musical instrument / musical instrument 
(c) unit of intensity of sound / unit of sound intensity 
(d) unit of elasticity / unit of elasticity
Show Answer
Ans. (C) 
Sol. The decibel (dB)

Q13. FM broadcasting service uses the range of frequency bands between - FM broadcast service uses 
which band frequency limit? 
(a) 109-139 MHz / 109-139 MHz 
(b) 54-75 MHz / 54-75 MHz 
(c) 76-87 MHz / 76-87 MHz 
(d) 88-108 MHz / 88-108 MHz
Show Answer
Ans. (D) 
Sol. FM broadcasting service uses the range of frequency bands between 88 to 108 MHz. There is a number of band allocation used around the globe:  
1. 87.5 - 108 MHz: - It is the "standard" VHF FM band. The one which is most widely used around the globe 
2. 76-90 MHz- This VHF FM band used in Japan 
3. 65.8 - 74.0 MHz- This VHF FM band is known as the OIRT band. It used in Eastern Europe although few other countries like Russia, Ukraine also used i t 

Q14. Following rays were used in the diagnosis of intestinal diseases. 
Which of the following rays are used in the diagnosis of intestinal diseases? 
(a) X-rays / X-ray 
(b) α-rays / α-rays 
(c) β-rays / β-rays 
(d) γ-rays / γ- rays
Show Answer
Ans. (A) 
Sol. X-rays are a form of electromagnetic radiations, which were used in the diagnosis of intestinal diseases.

Q15. CT scan is done by using- which of the 
following is done using CT scans? 
(a) Infra-red Rays / Infra-red rays 
(b) Ultrasonic waves / ultrasonic waves 
(c) Visible light / visible light 
(d) X-Rays / X-ray
Show Answer
Ans. (D) 
Sol. CT scan or computed tomography are special x-rays tests that produce cross-sectional images of the body using x-rays and a computer.

Q1. I-Water, II-Steel, III-Nitrogen- Arrange the speed of sound in the  
following medium i-water, II-steel, III-nitrogen-in ascending order. 
(a) III, II, I 
(b) III, I, II 
(c) I, III, II 
(d) II, I, III

Show Answer
Ans. (B) 
Sol. The speed of sound is different The speed of sound is maximum in solids while minimum in gas. The speed of sound in air at normal temperature and pressure is 332 m / s. The speed depends on the direction of which is travelling. The medium which has high density, the sound will travel faster in that medium.

Q2. The velocity of sound is maximum in- The maximum velocity of sound is  
in ______. 
(a) Air / Air 
(b) Liquid / Liquid 
(c) Metal / Metal 
(d) Vacuum / Vacuum
Show Answer
Ans. (C) 
Sol. The speed of sound is different The speed of sound is maximum in solids while minimum in gas. The speed of sound in air at normal temperature and pressure is 332 m / s. The speed depends on the direction of which is travelling. The medium which has high density, the sound will travel faster in that medium.

Q3 If Va, Vw and Vs are respectively the speed of sound in air, water and steel, then- 
if the speed of sound is Va, Vw and Vs respectively in air, water  , steel then-
(a) Va <Vw <Vs 
(b) ) Vs <Vw <Va 
(c) Vw <Vs <Va 
(d) Vs <Va <Vw
Show Answer
Ans. (A) 
Sol. As we know In general, sound travels faster in liquids than gases and faster in solids than in liquids.

Q4. In which medium the speed of sound is maximum at a temperature of around 20 ° C? 
In which medium does the speed of the sound be maximized at a maximum temperature of 20 degree Celsius? 
(a) Air / Air 
(b) Granite / Granite  
(c) Water / Water 
(d) Iron / Iron
Show Answer
Ans. (D) 
Sol. The speed of sound depends on the elasticity and density of the medium through which it is travelling. Greater the elastically and lower the density, the sound travels faster in that medium. At temperature of 20 ° C, the speed of sound is maximum in iron.

Q5. Sound waves-  
Sound waves- 
(a) Can travel in vacuum (can travel in vacuum) 
(b) Can travel only in solids (can travel only in concrete) 
(c) Can travel only in gases. (Only gases 
Can travel in (d) Can travel both in solid and gaseous medium (can travel in both concrete and gaseous mediums.
Show Answer
Ans. (D) 
Sol. Sound waves need to travel through a medium such as a solid, liquid or gas. The sound waves travel through the mediums by vibrating the molecules in the matter. The molecules in solids are packed very tightly but in liquids are not packed as tightly as solids, and in gases they are very loosely packed as tightly as solids, and in gases they are very loosely packed. The spacing of the molecules, able to travel faster than solid than gas. So sound waves can travel in solid, liquid and gaseous medium.

Q6. In which of the following options? 
Which of the following options can not be crossed by sound travel
(a) Water / Water 
(b) vacuum / vacuum 
(c) Iron / Iron 
(d) Air / Air
Show Answer
Ans. (B) 
Sol. Sound waves need a medium to travel. Vacuum is a situation of emptiness So due to the absence of any medium in this situation, the sound waves may not be travelled.

Q7 Bats can fly during dark nights and also prey. This is because - 
bats can fly during the darkness of the night and can also make prey. This is because-
(a) The pupil of their eyes is large / their pupil of the eyes is big. 
(b) Their night vision is very good / their night vision is very good 
(c) Every bird can do this / Every bird can do it. 
(d) They produce ultrasonic waves and are guided by them / they produce ultrasonic waves and are guided by them.
Show Answer
Ans. (D) 
Sol. Bats are a fascinating group of animals. They are one of the few mammals that can use ultrasonic voice to navigate. As they fly, make an ultrasonic (shouting) sound The returning echoes give the bats information about anything that is ahead of them, including the speed and size of a insect and which way it is going to go. This system of finding is called echolocation-locating things by their echoes.

Q8. The walls of the hall, built for music concerts 
should-be made for the walls of the hall,  music concerts-
(a) Amplify sound / enhanced sound 
(b) Transmit sound / voice communication 
(c) Reflect sound / reflective sound 
(d) Absorb sound / absorption sound
Show Answer
Ans. (D) 
Sol. The walls of the hall Most of the solid walls If the walls of concert hall reflects the sound, then audiences hear the echo sound. So to avoid this

Q9. The velocity of sound in air at 0 ° C is approximately - at 0 ° C 
in the air, the speed of sound is approximately ________. 
(a) 10 km / sec / 10 km / sec 
(b) 10 mile / min / 10 mile / min 
(c) 330 m / sec / 330m / sec 
(d) 3 × 1010 / sec. / 3 × 1010 / sec
Show Answer
Ans. (C) 
Sol. The speed of sound in air is approximately 331.5 m / s at 0 ° C or around 1200 km per hour.

Q10. Two astronauts can not hear each other on the moon's surface, because - 
two astronauts can not hear each other on the surface of the moon  , because-
(a) Their ears have stopped working on the moon / their ears stop working on the moon to give 
(b) No atmosphere on the moon / no atmosphere on the Moon 
(c) they wear special space suits on the moon / they wear special space suits on the Moon 
(d) the sound travels much more slowly on moon / Moon But the sound travels very slowly
Show Answer
Ans. (B) Sol. In order for sound to propagate from one place to another, it needs a medium or a fluid to move through. The air on the earth is allowed to move from one point to another. However, there is vacuum on surface of moon Thus, there is no sound on the moon

Q11. An astronaut can not hear his companion at the surface of the moon  
because--
(a) Produced frequencies are above the audio frequency / frequencies produced more than the audio frequency.        
(b) Temperature is too low during night and too high during day / night temperature is very low and during the day is very high. 
(c) There is no medium for sound propagation / sound transmission 
(d) There are many craters on the surface of the moon.
Show Answer
Ans. (C) 
Sol. In order for sound to propagate from one place to another, it needs a medium or a fluid to move through. The air on the earth is allowed to move from one point to another. However, there is vacuum on surface of moon Thus, there is no sound on the moon

Q12. In a Laser (say neon laser) all atoms emit the light waves of 
a laser (neon laser) emits all atomic light waves -
(a) Same frequency / similar frequency 
(b) Same amplitude / same dimension 
(c) ) Same phase / same phase 
(d) All the above / This all
Show Answer
Ans. (D) 
Sol. A laser (say neon laser) all the atoms emit the light waves of Same frequency, Same amplitude and Same phase.

Q13. Consider the following statements about ultrasonic waves:  
Consider the following statements about the ultrasonic waves to: 
Lk They Can Destroy Insects / they destroy insects. 
2. They can clean clothes by removing the dust. 
3. They can be used to treat disease. 
4. They can control automatic doors / they control automatic doors. 
Of the above statements    
-
(a) 1 and 2 are correct / 1 and 2 is true 
(b) 3 and 4 are correct / 3 and 4 is true 
(c) 1, 2 and 3 are correct / 1, 2 and 3 is true 
(d) All are correct / all is true
Show Answer
Ans. (D) 
Sol. Sound waves are longitudinal-mechanical wave. Sound wave is divided into three categories that cover different frequency range; Audible waves (20htz- 20,000htz), infrasonic waves (<20htz) and ultrasonic waves (> 20,000htz). Detecting of aircraft and submarine, determination of depth of sea etc.

Q14. Ultrasonics are sound waves of frequency The frequency of  
ultrasonic sound waves are _________. 
(a) Greater than 20,000 Hz / 20,000 Hz 
(b) Less than 10,000 Hz / 10,000 Hz 
(c) Equal to 1000 Hz / 1000 Hz 
(d) None of these None of these
Show Answer
Ans. (A) 
Sol. Sound waves are longitudinal-mechanical wave. Sound wave is divided into three categories that cover different frequency range; Audible waves (20htz- 20,000htz), infrasonic waves (<20htz) and ultrasonic waves (> 20,000htz). Detecting of aircraft and submarine, determination of depth of sea etc.

Q15. A biotechnique in which ultrasonic sound 
was used - Describe the name of the  biotechnic in which the ultrasonic sound is used- 
(a) Sonography / Sonography 
(b) ECG / ECG 
(c) EEG / E.E.G. 
(d) X-ray / X-ray
Show Answer
Ans. (A) 
Sol. Sonography or ultrasonography is an important means of clinical diagnosis. It is a diagnostic imaging technique based on the application of ultrasound. It is widely used in the field of medical science. It is used as a variety of information about the health of the mother during pregnancy, and the health and development of the embryo or foetus


Q1. Which of the following pairs is not correctly matched: Which of the following  
does not match correctly?
(A) Discovery of Meson / Mason's discovery  - Hideki Yukawa 
(b) Discovery of Positron / Positron search  - C. D. Anderson and U.F. Hess 
(c) Theory of energy production in the / Theory of Energy Production  - HA Bethe / H.A. Bethe 
(d) Synthesis of transuranic elements / Synthesis of transunuclear elements  - Enrico Fermi / Enrico Firmi

Show Answer
Ans. (D) 
Sol. In 1935, Meson particles were discovered by Japanese physicist Hideki Yukawa. Positron, the antiparticle or the antimatter counterpart of the electron was discovered by CD Anderson and UF Hess in 1932. In 1939, Hans Bethe described the nuclear reactors that power the sun and other stars. In synthesis of transuranic elements, Glenn T. Scaborg played an important role instead of Enrico Fermi. The fact is that he tried to make a transuranium element in 1934 in Rome but failed to do so.

Q2. Which of the following is not  
true:
(a) Theory of evolution was propounded by Charles Darwin. / The theory of evolution by Charles Darwin was interpreted 
(b) The breaking apart of the nucleus of an atom is called fusion The breakdown of an atom's nucleus is called fusion 
(c) 'dry ice' is nothing but solid carbon dioxide. / 'Dry ice' is nothing but solid carbon dioxide 
(d) Telephone was invented by Graham Bell. Telephone / Graham Bell was invented
Show Answer
Ans. (B) 
Sol. Option (b) is not correct It is the breaking apart of the nucleus of an atom is called fission not fusion. Fission is a radioactive decay process in which the nucleus of an atom splits in small parts.

Q3 One of these particles is claimed to have been invented by the Rebut the Einstein's theory of relativity. 
Which of these particles was invented to relate the theory of relativity? 
(a) Microwave Photon / Microwave Photon 
(b) Neutrino / neutrino 
(c) Liquid crystal / liquid crystal 
(d) Light emitting diode / light-emitting diode
Show Answer
Ans. (A) 
Sol. The two physicists Gunter Nimtz and Alfons Stahlhofen of the University of Koblenz, Germany claimed that the propelled microwave photons faster than the speed of light. This is the direct violation of a key content of Einstein's special theory of relativity that states under the circumstances

Q4. Cyclotrons are used to accelerate: 
cyclotron is used to 
speed up: (a) Neutrons / neutrons 
(b) Protons / protons 
(c) Atoms / atoms 
(d) Ions / ions
Show Answer
Ans. (B) 
Sol. Cyclotron is a machine used to accelerate charged particles such as alpha particles, deuteron, proton etc. up to a very high speed

Q5. Which water of the water is a gamma emitting isotope or not? 
Which of the following can be used to confirm whether there is a gamma-emitting isotope in drinking water? 
(a) Microscope / Microscope 
(b) Lead plate / Lead plate 
(c) Scintillation counter / Skin counting 
(d) Spectrophotometer / Spectrophotometer
Show Answer
Ans. (C) 
Sol. Scintillation counter is an instrument for detecting ionizing radiation by using the excitation effect of incident radiation. Radiation on a scintillator material and detecting light particles.

Q6. Among the following radiations, which has the highest energy? 
Of the following radiations, which has the highest energy 
(a) Visible / visibility 
(b) X-ray / x-ray 
(c) Ultra-violet / 
(d) Infra-red / Infrared
Show Answer



Ans. (B)  X-ray

Q7 The energy of sun is released due to which the energy of the sun is released  
-
(a) Nuclear Fission / Nuclear fission 
(b) Nuclear Fusion / nuclear fusion 
(c) Oxidation Reactions / oxidation reactions 
(d) Reduction Reactions / Reduction Reactions
Show Answer
Ans. (B) 
Sol. The Sun produces energy by nuclear fusion of hydrogen in the helium in its core. Since there is a huge amount of hydrogen in the core, these atoms stick together and fuse in a helium atom. This energy is then radiated from the solar system. This is the main source of energy Apart from that the gravitational compilation in stars

Q8. Stars obtained their energy from:  
Stars From whom to get their energies 
1. Nuclear fusion / nuclear fusion 
2. Gravitational compaction / gravitational contraction 
3. Chemical reaction / chemical reaction 
4. Nuclear fission / nuclear fission 
Select your answer from the given below:  
Choose your answer from the code below 
Code / Code: 
(a) 1 and 2 / 
(b) 1, 2 and 3 / 
(c) 1 and 4 / 
(d) 2 and 4 /
Show Answer
Ans. (A) 
Sol. The Sun produces energy by nuclear fusion of hydrogen in the helium in its core. Since there is a huge amount of hydrogen in the core, these atoms stick together and fuse in a helium atom. This energy is then radiated from the solar system. This is the main source of energy Apart from that the gravitational compilation in stars

Q9. Who discovered cloud chamber? 
Who discovered the cloud chamber? 
(a) Madam Curie / Madam Curie 
(b) Rutherford / Rutherford (c) Charles Thomson Rees Wilson / Charles Thomson Rees Wilson (d) Thomson / Thomson


Show Answer
Ans. (C) 
Sol. Charles Thomson Rees Wilson is a Scottish physicist, credited with the inventing the cloud chamber.

Q10. Which of the following 
stars is the source of renewable energy 
(a) Hydrogen changes in helium / hydrogen is converted into helium 
(b) Helium changes into hydrogen / helium hydrogen turns 
(c) decay of radioactive material / decay of radioactive material 
(d) Excess of oxygen which is helpful in burning and generate energy. In addition to oxygen / burning energy which helps in burning and producing
Show Answer
Ans. (A) 
Sol. The Sun produces energy by nuclear fusion of hydrogen in the helium in its core. Since there is a huge amount of hydrogen in the core, these atoms stick together and fuse in a helium atom. This energy is then radiated from the solar system. This is the main source of energy Apart from that the gravitational compilation in stars

Q11. Canal rays are:  
Canal rays are
(a) Positive in nature / Positive in nature 
(b) Negative in nature / Negative in nature 
(c) Neutral in nature / Neutral in nature 
(d) Not specified /
Show Answer
Ans. (A) 
Sol. An anode ray (also positive ray or canal ray) is a beam of positive ions that created by certain types of gas-discharge tubes. They were first observed in Crookes tubes during experiments by the German scientist Eugen Goldstein, in 1886.

Q12. What is the power of an artificial satellite? 
What is the source of electrical energy in an artificial satellite? 
(a) Solar cells / solar cells 
(b) Mini nuclear reactor / 
(c) Dynamo / dynamo 
(d) Thermopile / thermopile
Show Answer
Ans. (A) 
Sol. Solar (or photovoltaic) cells convert the sun's energy into electrical energy through photoelectric effect. Photoelectric effect is the ability of matter to emit electrons

Q13. Which one is used in solar cells? 
Which of the following is used in solar cells? 
(a) Silicon / Silicon 
(b) Cerium / 
Cereum (c) Astatine / Astatine 
(d) Vanadium / Vanadium
Show Answer
Ans. (A) 
Sol. Solar cells are the components of solar arrays that convert radiant light from the sun into electricity. Solar cells contain materials with semiconducting properties in which their electrons become excited and turned into an electric current when struck by sunlight. While there are a dozen of variation of solar cells, the two most common types are those made of crystalline silicon (both monocrystalline and polycrystalline) and those made with what is called thin technology. The majority (90%) of the solar cells on the market today made silicon.

Q14. Photovoltaic cells are:  
What are photovoltaic cells
(a) Solar cells / solar cell 
(b) Thermal cells / thermal cell 
(c) Sulfur cells / sulfur cells 
(d) Molar cells / molar cells
Show Answer
Ans. (A) 
Sol. The conversion of light energy into electricity is based on phenomenon called photovoltaic effect. A photovoltaic cell is the basic unit of the system where the photovoltaic effect is used to produce electricity from light energy. Silicon is the most widely used semiconductor material for building photovoltaic cell.

Q15. Where are mesons found:  
Mason invented whom:
(a) Cosmic rays / cosmic rays 
(b) X-rays / x-ray 
(c) Gamma rays / gamma rays 
(d) Laser beam / laser beam
Show Answer
Ans. (A) 
Sol. Mesons appear in nature only as short-lived products of very high-energy collisions between particles made of quarks, such as cosmic rays (high-energy protons and neutrons) and common matter.

Q1.The temperature is measured 
by which temperature is measured  by
(a) Altimeter / 
Ultimeter (b) Pyrometer / Pyrometer 
(c) Ammeter / Ammeter 
(d) Callipers / Calipers

Show Answer
Ans.(b)
Sol. Pyrometer is an instrument for measuring high temperatures, especially in furnaces and kilns.

Q2. Photovoltaic cells are? 
What are photovoltaic cells
(a) Solar cells / solar cells 
(b) thermal cells / thermal cells 
(c) Sulfur cells / sulfur cells 
(d) Molar cells / molar cells
Show Answer
Ans.(a)
Sol. The conversion of light energy into electrical energy is based on the phenomenon  called photov
oltaic effect. A photovoltaic cell is the basic unit of the system where the photovoltaic effect is utilized to produce electricity from light energy. Silicon is most widely used semiconductor material for construction photovoltaic cell.
Q3 When the door of the refrigerator is opened in a closed room, then: When the door of the fridge is opened in a  
locked room, then:
(a) Immediately room becomes cooler / sudden room cools 
(b) the temperature of room falls The gradual fall 
of room temperature (c) the temperature of the room is not affected / the temperature of the room is not affected 
(d) the room becomes hotter gradually / the room gradually gets heated
Show Answer
Ans.(d)
Sol. The reason is that with the door open the temperature will start to rise inside the refrigerator. The thermostat will kick in and try to cool it back down. This means the motor is running which means heat is being added to the room.

Q4.The SI unit of latent heat is the SI unit of the incubator  
heat-
(a) cal-g 
(b) cal / ° C 
(c) joule / kg- joule / kg 
(d) none of these / any of these No
Show Answer
Ans.(c)
Sol. The SI unit of latent heat is joule per kilogram

Q5. Minus 40 degrees centigrade is equal to __ degrees Fahrenheit. 
Minimum 40 degree centigrade is equal to __definehouse. 
(a) 104 
(b) 122 
(c) - 40 
(d) None of these / None of these
Show Answer
Ans.(c)
Sol. Minus 40 degree centigrade is equal to -40 degree Fahrenheit.
  -40°C×9/5+32
  = -40°F

Q6. The safest temperature for keeping food fresh in  a refrigerator is 
how the safe temperature to keep food in the refrigerator fresh 
(A) 0 ° C - 4 ° C 
(B) 8 ° C - L2 ° C (C) 20 ° C - 25 ° C (d) 10 ° C -15 ° C

Show Answer

Ans.(a)

Sol. The lower temperature slows the growth of microorganisms already in the food. According to international standards safest temperature for keeping food fresh in a refrigerator is 0°C - 4°C.



Q7 Why does food cook faster in a pressure cooker? 
The food cooker can be cooked fast, why -
(a) The increased pressure increases the boiling point. / Increasing pressure increases the boiling point 
(b) Does not waste steam / Vapor does not waste 
(c) The food is cooked quickly by steam. / Dies quickly by steam 
(d) The water boils at constant temperature. / Water constantly boils at the same temperature
Show Answer
Ans.(a)
Sol. The pressure inside the pressure cooker is very high. This raises the boiling point of water and the temperature inside the cooker is higher them 100°C which results in faster cooking of food.

Q8. A body floats at 4 ° C water. If the temperature reaches 100 ° C then- the 
body floats in 4 ° C water. If the temperature reaches 100 ° C then-
(a) The body will sink / body will be submerged 
(b) No change / no change will happen 
(c) More part of the body will submerge / excess body part will be drowned 
( d) The body will float freely / body will float independently
Show Answer
Ans.(a)
Sol. When the water is heated, its density decreases. The density of the water at 100°C is at the lowest, so the body will sink. Water density is maximum at 4°C, so the body will float.

Q9. Pure water freezes at what temperature? 
At what temperature does the pure water accumulate?    
(a) 47 F 
(b) 32 F 
(c) 0 F 
(d) 19 F
Show Answer
Ans.(b)
Sol. Water freezes at 32 degrees Fahrenheit or 0 degrees Celsius.

Q10. Xeric condition refers to-  
the reference to the zeric position is 
(a) low temperature / low temperature 
(b) Inadequate supply of water / insufficient supply of water 
(c) high evaporation / high evaporation 
(d) extreme temperature / maximum temperature
Show Answer
Ans.(b)
Sol. Xeric denoting conditions characterized by an inadequate supply of water. Xeric conditions exist in arid habitats, extremely cold habitats, and in salt marshes.

Q11.The temperature of the filament of lighted electric bulb is usually: 
Filament of light  bulb is generally the temperature
(a) 100 ° C to 500 ° C 
(b) 1000 ° C to 1500 ° C 
(c) 2500 ° C to 3000 ° C 
(d) 4000 ° C to 5000 ° C
Show Answer
Ans.(c)
Sol. Tungsten metal is used as filament in electric bulb. When electric current flows through it, its temperature goes up to 2500°C from 3000°C. Generally, electric bulbs convert only 5% to 10% of electric energy to light.

Q12. The conductivity of a semi-conductor at zero degree Kelvin is- What  
is the conduction of a semiconductor in zero degree Kelvin-
(a) 10 ^ 5 ohm / ohm 
(b) 10 ^ (- 1) ohm / ohm 
(c) 10 ^ (-5) ohm / ohm 
(d) zero / zero
Show Answer
Ans.(d)
Sol.The materials [Germanium, Silicon] whose electrical conductivity varies between conductors and dielectric are called semiconductors. At absolute zero temperature, a semiconductor behaves like a perfect dielectric.

Q13. The highest temperature 
 achieved by a super conductor  is -
(a) 24 K 
(b) 138 K 
(c) 150 K 
(d) 300 K
Show Answer
Ans.(b)
Sol.  Where as ordinary or metallic super conductors usually have transition temperature (temperature below which they are super conductive) below 30k and must be cooled using liquid helium in order to achieve super conductivity. High temperature super conductors have been observed with transition temperature as high as 138 K.

Resistance of semiconductor on heating of QM.The resistance of a semiconductor on heating  
:
(a) Remains / remains the same 
(b) Decreases / decreases 
(c) Increases / Increases 
(d) None of the above / Out of above No one
Show Answer
Ans.(b)
Sol. With the increase in temperature, the conductivity of the semi-conductor material increases and  resistance decreases.

Q15. What is absolute zero temperature? 
What is absolute zero temperature? 
(a) The starting point of any temperature scale / the starting point of any temperature 
(b) No more heat can be removed (no other heat can be removed 
(c) The temperature at the vapor of any liquid substance is condensed ( 
The temperature at which the vapor of any liquid is dense (d) The temperature at which all materials are in vapor form. (The temperature at which all matter is in vapor form.
Show Answer
Ans.(b)
Sol. Absolute zero is defined as the point where no more heat can be removed from a system, according to the absolute or thermodynamic temperature scale. This corresponds to 0 K or -273.15°C.