JEE Physics Thermal Properties Of Matter MCQs Set A

Question: Temperature is a measure of

• a) Hotness or coldness
• b) Potential energy
• c) Thermal energy
• d) Heat possessed by a body

Answer: Hotness or coldness

Question: The readings of a bath on Celsius and Fahrenheit thermometers are in the ratio 2 : 5. The temperature of the bath is

• a) 45.71°C
• b) 40°C
• c) 26.66°C
• d) –26.66°C

Answer: 45.71°C

Question: The pressure of a gas filled in the bulb of a constant volume gas thermometer at temperatures 0°C and 100°C are 27.50 cm and 37.50 cm of Hg respectively. At an unknown temperature the pressure is 32.45 cm of Hg. Unknown temperature is

• a) 49.5°C
• b) 29.6°C
• c) 39°C
• d) 30°C

Answer: 49.5°C

Question: A graph is plotted by taking pressure along y-axis and centigrade temperature along x-axis for an ideal gas at constant volume. x intercept of the graph is

• a) –273.15ºC
• b) –273.15 K
• c) –273ºC
• d) –273 K

Answer: –273.15ºC

Question:  A hole is drilled in a copper sheet. The diameter of hole is 4.24 cm at 27.0°C. Diameter of the hole when it is heated to 35°C is

• a) More than 4.24 cm
• b) Less than 4.24 cm
• c) Equal to 4.24 cm
• d) Data insufficient

Answer: More than 4.24 cm

Question: The density of water is maximum at

• a) 39.2°F
• b) 4°F
• c) 0°C
• d) 273 K

Answer: 39.2°F

Question: On heating a uniform metallic cylinder length increases by 3%. The area of cross-section of its base will increase by

• a) 6%
• b) 9%
• c) 3%
• d) 1.5%

Answer: 6%

Question: A circular metallic disc of radius R has a small circular cavity of radius r as shown in figure. On heating the system

• a) Both R and r increases
• b) R increases and r decreases
• c) R decreases and r increases
• d) Both R and r decreases

Answer: Both R and r increases

Question: If in winter season the surface temperature of lake is 1°C, the temperature at the bottom of lake will be

• a) 4°C
• b) 1°C
• c) 0°C
• d) All values less than 1°C are possible

Answer: 4°C

Question:

• a) Zero
• b) 18 × 10³ N
• c) 36 × 10³ N
• d) 12 × 10³ N

Answer:  Zero

Question:

• a) 36.28 s
• b) 82.35 s
• c) 3.828 s
• d) 321.5 s

Answer: 36.28 s

Question:

• a)

  

• b)

  

• c)

  

• d)

  

Answer:

Question: The coefficient of volume expansion of glycerin is 49 × 10^–5 K^–1. The fractional change in the density on a 30°C rise in temperature is

• a) 1.47 × 10^–2
• b) 1.47 × 10^–3
• c) 1.47 × 10^–1
• d) 1.47 × 10^–4

Answer:  1.47 × 10^–2

Question:

• a)

  

• b)

  

• c)

  

• d)

  

Answer:

Question:

• a) –0.042%
• b) –0.035%
• c) 0.012%
• d) –0.018%

Answer: –0.042%

Question: In engines water is used as coolant, because

• a) It has high specific heat
• b) It's good conductor of heat energy
• c) It has low density
• d) It’s bad conductor of heat energy

Answer: It has high specific heat

Question: Which of the following material is used to make calorimeter?

• a) Metal
• b) Superconductor
• c) Ebonite
• d) Glass

Answer: Metal

Question: The thermal capacity of 100 g of aluminum (specific heat = 0.2 cal/g°C) i20 cal/°Cs

• a) 20 cal/°C
• b) 0.002 cal/°C
• c) 200 cal/°C
• d) 100 cal/°C

Answer: 20 cal/°C

Question: Select correct statement related to heat

• a) Heat is a energy which flows due to temperature difference
• b) Hot water contains more heat as compared to cold water
• c) Heat is possessed by a body
• d) All of these

Answer: Heat is a energy which flows due to temperature difference

Question: A block of ice at –12°C is slowly heated and converted into steam at 100°C. Which of the following curves best represents the event?

• a)

  

• b)

  

• c)

  

• d)

  

Answer:

More Questions...................................

Question: The water equivalent of 20 g of aluminium (specific heat 0.2 cal g^–1 °C^–1 ), is

• a) 4 g
• b) 40 g
• c) 8 g
• d) 160 g

Answer: 4 g

Question: 100 g of ice (latent heat 80 cal g^–1, at 0°C) is mixed with 100 g of water (specific heat 1 cal g^–1 °C^–1) at 80°C. The final temperature of the mixture will be

• a) 0°C
• b) 40°C
• c) 80°C
• d) < 0°C

Answer: 0°C

Question: 200 g of ice at –20°C is mixed with 500 g of water at 20°C in an insulating vessel. Final mass of water in vessel is (specific heat of ice = 0.5 cal g^–1°C^–1)

• a) 600 g
• b) 400 g
• c) 200 g
• d) 700 g

Answer: 600 g

Question: Which of the following material is most suitable for cooking utensil?

• a) High conductivity and low specific heat
• b) High conductivity and high specific heat
• c) Low conductivity and low specific heat
• d) Low conductivity and high specific heat

Answer: High conductivity and low specific heat

Question: Which of the following factors affect the thermal conductivity of a rod?

• a) Material of rod
• b) Area of cross-section
• c) Length of rod
• d) All of these

Answer: Material of rod

Question: What is the dimensional formula for thermal resistance?

• a) [M^–1 L^–2 T³ K]
• b) [ML^–3 T² K^–1]
• c) [ML² T^–2 K^–1]

Answer: [M^–1 L^–2 T³ K]

Question:

• a)

  

• b)

  

• c)

  

• d)

  

Answer:

Question: Four rods of same material with different radii r and length l are used to connect two reservoirs of heat at different temperatures. Which one will conduct maximum heat?

• a) r = 2 cm, l = 1/2 m
• b) r = 2 cm, l = 2 m
• c) r = 1 cm, l = 1 m
• d) r = 1 cm, l = 1/2 m

Answer: r = 2 cm, l = 1/2 m

Question:

• a)

  

• b)

  

• c)

  

• d)

  

Answer:

Question: A cylinder of radius R made of a material of thermal conductivity K₁ is surrounded by a cylindrical shell of inner radius R and outer radius 2R made of a material of thermal conductivity K₂. The two ends of the combined system are maintained at two different temperatures. There is no loss of heat across the cylindrical surface and the system is in steady state. The effective thermal conductivity of the system is

• a)

  

• b)

  

• c)

  

• d) K₁+ K₂

Answer:

Question: Four rods of same material and having the same cross section and length have been joined, as shown. The temperature of the junction of four rods will be

• a) 45°C
• b) 60°C
• c) 30°C
• d) 20°C

Answer: 45°C

Question: Why it is more hotter for same distance over the top of a candle than it in the side of its flame?

• a) Convection takes more heat in upward direction
• b) Radiation and conduction both contribute in transferring heat upwards
• c) Heat is maximum radiated in upward direction
• d) Conduction of heat in air is upward

Answer: Convection takes more heat in upward direction

Question: In gravity free space heat transfer is not possible by

• a) Convection
• b) Conduction
• c) Radiation
• d) None of these

Answer: Convection

Question: Which factor does not affect convection?

• a) The thermal conductivity of carrying medium
• b) The rate of movement of carrying medium
• c) Temperature difference
• d) The volumetric specific heat of carrying medium

Answer: The thermal conductivity of carrying medium

Question: A polished plate with rough black spot is heated to a high temperature and then taken to a dark room, then

• a) Spot will appear brighter than the plate
• b) Both will appear equally brighter
• c) Spot will appear darker than the plate
• d) Both will not be visible

Answer: Spot will appear brighter than the plate

Question: Select the incorrect statement

• a) A body does not radiate when its temperature is below 0ºC
• b) A colder body can radiate heat to the hotter surroundings
• c) A good reflector is a bad radiator
• d) A body radiates at all temperatures except 0 K

Answer: A body does not radiate when its temperature is below 0ºC

Question: “A good absorber is a good emitter” is explained by

• a) Kirchhoff’s law
• b) Wien’s law
• c) Stefan’s law
• d) Newton’s law of cooling

Answer: Kirchhoff’s law

Question: The rate of radiation of energy from a hot object is maximum, if its surface is

• a) Black and rough
• b) White and smooth
• c) Black and smooth
• d) White and rough

Answer: Black and rough

Question: Two balls of same material and same surface finish have their diameters in the ratio 1 : 2. They are heated to the same temperature and are left in a room to cool by radiation, then the initial rate of loss of heat

• a) For larger ball is four times that of the other ball
• b) For larger ball is twice that of other ball
• c) For larger ball is half that of other ball
• d) Will be same for the balls

Answer: For larger ball is four times that of the other ball

Question: A black body, which is at a high temperature T K, thermal radiation emitted at the rate of E W/m². If the temperature falls to T/4 K, the thermal radiation emitted in W/m² will be

• a) E/256
• b) E/64
• c) E/4
• d) E

Answer:  E/256

Question: A sphere, a cube and a thin circular plate, all made of the same mass and finish are heated to a temperature of 200°C. Which of these objects will cool slowest, when left in air at room temperature?

• a) The sphere
• b) The circular plate
• c) The cube
• d) All will cool at same rate

Answer: The sphere

Question: A body cools down from 80°C to 60°C in 10 minutes when the temperature of surroundings is 30°C. The temperature of the body after next 10 minutes will be

• a) 48°C
• b) 30°C
• c) 50°C
• d) 52°C

Answer: 48°C

Question:

• a)

  

• b)

  

• c)

  

• d)

  

Answer:

Question:

• a)

  

• b)

  

• c)

  

• d)

  

Answer:

Question:

• a) 4 : 1
• b) 1 : 4
• c) 16 : 1
• d) 8 : 1

Answer: 4 : 1

Question: If temperature of sun is decreased by 1 % then the value of solar constant will change by

• a) –4%
• b) 2%
• c) –2%
• d) 4%

Answer: –4%

Question: The value of solar constant is

• a) 20 kcal m^–2 minute^–1
• b) 200 Wm^–2
• c) 2 kWm^–2
• d) 2 kcal m^–2 minute^–1

Answer: 20 kcal m^–2 minute^–1

Question: A uniform thermometre scale is at steady state with its 0 cm mark at 20°C and 100 cm mark at 100°C. Temperature of the 60 cm mark is

• a) 68°C
• b) 48°C
• c) 52°C
• d) 58°C

Answer:  68°C

Question:

• a) 1.2 × 10^–5/°C
• b) 0.6 × 10^–5/°C
• c) 0.75 × 10^–5/°C
• d) 1.5 × 10^–5/°C

Answer: 1.2 × 10^–5/°C

Question: Coefficient of linear expansion of a vessel completely filled with Hg is 1 × 10^–5/°C. If there is no overflow of Hg on heating the vessel, then coefficient of cubical expansion of Hg is

• a) 

  

• b) Data is insufficient
• c)

  

• d)

  

Answer:

Question: A metallic tape gives correct value at 25ºC. A piece of wood is being measured by this metallic tape at 10ºC. The reading is 30 cm on the tape, the real length of wooden piece must be

• a) < 30 cm
• b) 30 cm
• c) > 30 cm
• d) Data is not sufficient

Answer: < 30 cm

Question: In a thermostat two metal strips are used, which have different

• a) Coefficient of linear expansion
• b) Area of cross-section
• c) Length
• d) Mass

Answer: Coefficient of linear expansion

Question: The coefficient of linear expansion of a crystalline substance in one direction is 2 × 10^–4/°C and in every direction perpendicular to it is 3 × 10^–4/°C. The coefficient of cubical expansion of crystal is equal to

• a) 8 × 10^–4/°C
• b) 7 × 10^–4/°C
• c) 4 × 10^–4/°C
• d) 5 × 10^–4/°C

Answer: 8 × 10^–4/°C

Question: The molar specific heat at constant pressure of an ideal gas is (7/2)R. The ratio of specific heat at constant pressure to that at constant volume is

• a)

  

• b)

  

• c)

  

• d)

  

Answer:

Question:   A bullet of mass 10 g moving with a speed of 20 m/s hits an ice block of mass 990 g kept on a frictionless floor and gets stuck in it. How much ice will melt if 50% of the lost KE goes to ice? (initial temperature of the ice block and bullet = 0°C)

• a) 0.003 g
• b) 0.004 g
• c) 0.002 g
• d) 0.001 g

Answer: 0.003 g

Question: 50 g ice at 0°C is dropped into a calorimeter containing 100 g water at 30°C. If thermal capacity of calorimeter is zero then amount of ice left in the mixture at equilibrium is

• a) 12.5 g
• b) 25 g
• c) 10 g
• d) 20 g

Answer: 12.5 g

Question:

• a) C_p– C_v= R/M
• b) C_p– C_v= R
• c) C_p– C_v= S
• d) None of these

Answer: C_p– C_v= R/M

Question: Heat is being supplied at a constant rate to the sphere of ice which is melting at the rate of 0.1 gm/s. It melts completely in 100 s. The rate of rise of temperature thereafter will be

• a) 0.8°C/s
• b) 3.2°C/s
• c) 2.1°C/s
• d) 0.4°C/s

Answer: 0.8°C/s

Question: In a calorimeter of water equivalent 20 g, water of mass 1.1 kg is taken at 288 K temperature. If steam at temperature 373 K is passed through it and temperature of water increases by 6.5°C then the mass of steam condensed is

• a) 11.7 g
• b) 15.7 g
• c) 18.2 g
• d) 17.5 g

Answer: 11.7 g

Question: Heat energy at constant rate is given to two substances P and Q. If variation of temperature (T) of substances with time (t) is as shown in figure, then select the correct statement.

• a) Specific heat of Q is greater than P
• b) Data is insufficient to predict it
• c) Specific heat of P is greater than Q
• d) Both have same specific heat

Answer: Specific heat of Q is greater than P