## Class 11 Physics MCQs Thermal Properties of Matter for JEE/NEET

Here, you will get Class 11 Physics MCQ of Chapter 11 Thermal Properties Of Matter for cracking JEE and NEET/AIIMS. By solving these MCQs of Class 11 Physics Chapter 11 Thermal Properties Of Matter, you will get the confidence to crack JEE or NEET. Practice MCQ Questions for Class 11 Physics with Answers on a daily basis and score well in exams.

## Thermal Properties Of Matter Class 11 MCQs Questions with Answers

A black body at hot temperature at 227°C radiates heat at a rate of 5 cal/cm²s. at a temperature of 727°C the rate of heat radiated per unit area will be
(a) 50 cal/cm²s
(b) 250 cal/cm²s
(c) 80 cal/cm²s
(d) 100 cal/cm²s

Two stars A and B radiate maximum energy at 3600°A and 3600°A respectively. Then the ratio of absolute temperatures of A and B is
(a) 256 : 81
(b) 81 : 256
(c) 3 : 4
(d) 4 : 3

A cup of tea cools from 80°C to 60°C in one minute. The ambient temperature is 30°C. in cooling from 60°C to 50°C, it will take.
(a) 50 sec
(b) 90 sec
(c) 60 sec
(d) 30 sec

The earth intercepts approximately one billionth of the power radiated by the sun. if the surface temperature of the sun were to drop by a factor of 2, the average radiant energy incident on earth per second would reduce by factor of
(a) 2
(b) 4
(c) 8
(d) 16

A person with dark skin as compared to a person with white skin will experience
(a) Less heat and less cold
(b) More heat and more cold
(c) More heat and less cold
(d) Less heat and more cold

Answer: (b) More heat and more cold

The reading of Centigrade thermometer coincides with that of Fahrenheit thermometer in a liquid. The temperature of the liquid is
(a) 40°C
(b) 100°C
(c) 313°C
(d) 0ºC

4200 J of work is required for
(a) increasing the temperature of 100 g of water through 10°C
(b) increasing the temperature of 1 kg of water through 10°C
(c) increasing the temperature of 500 g of water through 10°C
(d) increasing the temperature of 10 g of water through 10°C

Answer: (a) increasing the temperature of 100 g of water through 10°C

The best ideal black body is
(a) Lamp of charcoal heated to high temperature
(b) Metal coated with a black dye
(c) Glass surface coated with coalter
(d) Hollow enclosure blackened inside and having a small hole

Answer: (d) Hollow enclosure blackened inside and having a small hole

Two marks on a glass rod 10 cm apart are found to increase their distance by 0.08 mm when the rod is heated from 0°C to 100°C. A flask made of the same glass as that of rod measures a volume of 1000 cc at 0°C. The volume it measures at 100°C in cc is
a) 1002.4
b) 1008.2
c) 1004.2
d) 1006.4

Which of the following statements regarding specific heat capacity of a substance are correct ? It depends on
I. mass of substance.
II. nature of substance.
III. temperature of substance.
IV. volume of substance.
(a) II and III
(b) None of these
(c) I and II
(d) III and IV

A liquid with coefficient of cubical expansion γ is contained in a vessel having coefficient of linear expansion γ/7. When heated, what will happen to the level of the liquid in the vessel?
(a) It falls
(b) It rises
(c) Remains unchanged
(d) It may rise or fall depending upon the nature of the container

A metallic ball has a spherical cavity at its centre. If the ball is heated, what happens to the cavity?
(a) Its volume decreases
(b) Its volume increases
(c) Its volume remains unchanged
(d) Its volume may increase or decrease depending upon the nature of the metal

One gram of ice is mixed with lg of steam. After thermal equilibrium, temperature of the mixture is
(a) 0°C
(b) 100°C
(c) 75°C
(d) 50°C

Two bars of copper having same length but an equal diameter are heated to the same temperature. The change in length will be:
(a) more in thicker bar
(b) more in thinner bar
(c) same for both
(d) determined by the ratio of length and diameter of the bars

The latent heat of vaporization of a substance is always
(a) greater than its latent heat of fusion
(b) less than its latent heat of fusion
(c) greater than its latent heat of sublimation
(d) equal to its latent heat of sublimation

Answer: (a) greater than its latent heat of fusion

A liquid having coefficient of cubical expansion y is filled in the container having coefficient of linear expansion a. If liquid overflows on heating, then which one is correct?
(a) γ = 2α
(b) γ > 3α
(c) γ < 3α
(d) γ = 2α

The density of water at 20°C is 998 kg m-3 and that at 40°C is 992 kg m-3. The coefficient of cubical expansion of water is
(a) 0.2 × 10-40C-1
(b) 0.6 × 10-40C-1
(c) 3.02 × 10-40C-1
(d) 0.4 × 10-40C-1

A beaker is completely filled with water at 4°C. It will overflow
(a) when heated but not when cooled
(b) when cooled but not when heated
(c) neither when heated nor when cooled
(d) both when cooled or heated

Answer: (d) both when cooled or heated

The top of lake is frozen as the atmospheric temperature is -10°C. The temperature at the bottom of the lake is most likely to be
(a) 0°C
(b) -4°C
(c) 4°C
(d) -10°C

A circular disc is heated. Its M.I. about an axis passing through its centre and perpendicular to its plane
(a) increases
(b) decreases
(c) remains same
(d) first increases and then decreases

A bucket full of hot water is kept in a room and it cools from 75°C to 70°C in t1 minutes from 70°C to 65°C in t2 minutes and from 65°C to 60°C in t3 minutes; then
(a) t1 – t2 = t3
(b) t1 < t2 < t3
(c) t1 > t2 > t3
(d) t1 < t2 > t3

Answer: (b) t1 < t2 < t3

The good absorber of heat are
(a) Non-emitter
(b) Poor-emitter
(c) Good-emitter
(d) Highly polished

A surface at temperature T0°K receives power P by radiation from a small sphere at temperature T >> T0 and at a distance d. if both T and d are doubled, the power received by surface will becomes approximately
(a) P
(b) 2p
(c) 4p
(d) 16p

Co-efficient of reflection, coefficient of absorption and coefficient transmission are related as
(a) a + r + 1 = 1
(b) a + r + t1 1
(c) a + r = -t
(d) a1 r + 1

Answer: (a) a + r + 1 = 1

The earth receives at its surface radiation from the sun at the rate of 1400 W/m². the distance of the centre of the sun from the surface of the earth is 1.5 1011 m and the radius of the sun is 7.0 108 m. treating sun as a black body, it follows from the above data that its surface temperature is,
(a) 5801 K
(b) 106 K
(c) 50.1 K
(d) 2801 C

Newton’s law of cooling is applicable for
(a) small excess of temperature over the surrounding
(b) large excess of temperature over the surrounding
(c) None of these
(d) any excess of temperature over the surrounding

Answer: (a) small excess of temperature over the surrounding

A metal sheet with a circular hole is heated. The hole
(a) gets larger
(b) gets deformed
(c) gets smaller
(d) None of these

Assertion: The triple point of water is a standard fixed point in modern thermometry.
Reason: The triple point of a substance is unique i.e. it occurs at one particular set of values of pressure and temperature
(a) Assertion is correct, reason is correct; reason is a correct explanation for assertion
(b) Assertion is incorrect, reason is correct
(c) Assertion is correct, reason is correct; reason is not a correct explanation for assertion
(d) None of these

Answer: (a) Assertion is correct, reason is correct; reason is a correct explanation for assertionK

Sweet makers do not clean the bottom of cauldron because
(a) black and rough surface absorbs more heat
(b) absorption power of black and bright surface is more.
(c) transmission power of black and rough surface is more.
(d) emission power of black and bright surface is more

Answer: (a) black and rough surface absorbs more heat

A metal piece heated to T1°K. The temperature of the surrounding is T2°K. the heat in the surrounding due to radiation is proportional to
(a) (T14 – T24)
(b) (T1 – T2)4
(c) (T14 + T24)
(d) (T13 – T23)

A body cools from 50°C to 46°C in 5 minutes and to 40°C in the next 10 minutes. The surrounding temperature is
(a) 30°C
(b) 28°C
(c) 36°C
(d) 32°C

The temperature of a piece of metal is raised from 27°C to 51.2°C. the rate at which metal radiates energy increases nearly
(a) 1.36 times
(b) 2.36 times
(c) 3.36 times
(d) 4.36 times

An iron tyre is to be fitted on to a wooden wheel 1m in diameter. The diameter of tyre is 6 mm smaller than that of wheel. The tyre should be heated so that its temperature increases by a minimum of (the coefficient of cubical expansion of iron is 3.6 × 10–5/°C)
(a) 500°C
(b) 334°C
(c) 1000°C
(d) 167°C

Unit of Stefans constant is given by
(a) W/ m K²
(b) W/ m² K²
(c) W²/ m² K4
(d) W/ mK

Emissivity of a perfectly black body is
(a) 1
(b) 2
(c) 5
(d) 0

Assertion : Water kept in an open vessel will quickly evaporate on the surface of the moon.
Reason : The temperature at the surface of the moon is much higher than boiling point of the water.
(a) Assertion is correct, reason is incorrect
(b) None of these
(c) Assertion is correct, reason is correct; reason is not a correct explanation for assertion
(d) Assertion is correct, reason is correct; reason is a correct explanation for assertion

Answer: (a) Assertion is correct, reason is incorrect

For which of the following process, the thermal conduction is maximum?
(a) Combustion
(c) Convection
(d) Conduction

A quantity of heat required to change the unit mass of a solid substance, from solid state to liquid state, while the temperature remains constant, is known as
(a) latent heat of fusion
(b) sublimation
(c) latent heat
(d) hoar frost

Answer: (a) latent heat of fusion

Absorptive power of a perfectly black body is
(a) Zero
(b) Infinity
(c) One
(d) Constant