EASY

Earn 100

Observe the following temperature Vs. time graph and fill in the blank:

During transition of solid phase to liquid, the object absorbs (electric \chemical \heat) energy, but its temperature does not increase.

100% studentsanswered this correctly

Important Questions on Thermal Properties of Matter

HARD

Physics>Heat and Thermodynamics>Thermal Properties of Matter>Change of State

Explain the following temperature versus time graph:

Question Image

HARD

Physics>Heat and Thermodynamics>Thermal Properties of Matter>Change of State

A thermally insulated cubical box of side length $20 cm$ and wall thickness $2 cm$ containing $2 kg$ of ice is closed on all sides. The mass of ice melted in $10$ hours is (Thermal conductivity of the material of the box $= 0.01 {Wm}^{- 1} K^{- 1},$ latent heat of ice $= 360 \times 10^{3} J {kg}^{- 1}$ and ambient temperature $= 40 ° C$ )

EASY

Physics>Heat and Thermodynamics>Thermal Properties of Matter>Change of State

Heat required to melt $1 g$ of ice is $80 cal$ . A man melts $60 g$ of ice by chewing in one minute. His power is______

EASY

Physics>Heat and Thermodynamics>Thermal Properties of Matter>Change of State

If minimum possible work is done by a refrigerator in converting 100 grams of water at

0 ° C

to ice, how much heat (in calories) is released to the surroundings at temperature

27 ° C

(Latent heat of ice

= 80 Cal / gram

) to the nearest integer?

MEDIUM

Physics>Heat and Thermodynamics>Thermal Properties of Matter>Change of State

A thermally insulated vessel contains

150 g

of water at

0 ° C

. Then the air from the vessel is pumped out adiabatically. A fraction of water turns into ice and the rest evaporates at

0 ° C

itself. The mass of evaporated water will be closest to: (Latent heat of vaporization of water

= 2.10 \times 10^{6} J k g^{- 1}

and Latent heat of Fusion of water

= 3.36 \times 10^{5} J k g^{- 1}

)

EASY

Physics>Heat and Thermodynamics>Thermal Properties of Matter>Change of State

A steam engine intakes $50 g$ of steam at $100 ° C$ per minute and cools it down to $20 ° C$ . If latent heat of vaporization of steam is $540 cal g^{- 1}$ , then the heat rejected by the steam engine per minute is _____ $\times 10^{3} cal$

(Given : specific heat capacity of water : $1 cal g^{- 1} {{}^{\circ}C}^{- 1}$ )

HARD

Physics>Heat and Thermodynamics>Thermal Properties of Matter>Change of State

10 H

inductor carries a current of

20 A

. If the energy stored in this inductor melts ice at

0 ° C,

then the mass of the ice melted is

[

Latent heat of ice

= 2.26 \times 10^{3} J {kg}^{- 1}]

EASY

Physics>Heat and Thermodynamics>Thermal Properties of Matter>Change of State

The physical quantity that determines whether or not a given system

A

is in thermal equilibrium with another system

B

is called

EASY

Physics>Heat and Thermodynamics>Thermal Properties of Matter>Change of State

In an experiment, a sphere of aluminium of mass

0.20 kg

is heated up to

150 ° C

. Immediately, it is put into water of volume

150 cc

27^{o} C

kept in a calorimeter of water equivalent to

0.025 kg

. The final temperature of the system is

40^{o} C

. The specific heat of the aluminium is(take

4.2 Joule = 1 calorie

)

MEDIUM

Physics>Heat and Thermodynamics>Thermal Properties of Matter>Change of State

1 kg

of water, at

20 ° C

is heated in an electric kettle whose heating element has a mean (temperature averaged) resistance of

20 Ω .

The rms voltage in the mains is

200 V

. Ignoring heat loss from the kettle, time taken for water to evaporate fully is close to
[ Specific heat of water

= 4200 J {kg}^{- 1} ° C^{- 1}

Latent heat of water

= 2260 k J k g^{- 1}

]

MEDIUM

Physics>Heat and Thermodynamics>Thermal Properties of Matter>Change of State

50 g

of ice at

0 ° C

is mixed with

50 g

of water at

80 ° C

. If the latent heat of ice is

80 cal g^{- 1}

and specific heat of water is

1 cal g^{- 1} ° C^{- 1}

, then the final temperature of mixture is

EASY

Physics>Heat and Thermodynamics>Thermal Properties of Matter>Change of State

A piece of ice falls from a height

h

so that it melts completely. Only one-quarter of the heat produced is absorbed by the ice and all energy of ice gets converted into heat during its fall. The value of

h

is:
(Latent heat of ice is

3.4 \times 10^{5} {J kg}^{- 1}

and

g = 10 {N kg}^{- 1}

)

HARD

Physics>Heat and Thermodynamics>Thermal Properties of Matter>Change of State

Two rectangular blocks, having identical dimensions, can be arranged either in configuration

I

or in configuration

I I

as shown in the figure. One of the blocks has thermal conductivity

K

and the other

2 K

. The temperature difference between the ends along the x-axis is the same in both the configurations. It takes

9 s

to transport a certain amount of heat from the hot end to cold end in the configuration

I

. The time to transport the same amount of heat in the configuration

II

MEDIUM

Physics>Heat and Thermodynamics>Thermal Properties of Matter>Change of State

A solid metal weighing

150 g

melts at its melting point of

800 ° C

by providing heat at the rate of

100 W

. The time taken for it to completely melt at the same temperature is

4 \min

. What is the specific latent heat of fusion of the metal?

EASY

Physics>Heat and Thermodynamics>Thermal Properties of Matter>Change of State

If pressure increased on a piece of wax, the melting point of wax

HARD

Physics>Heat and Thermodynamics>Thermal Properties of Matter>Change of State

An earthen pitcher used in summer cools water in it essentially by evaporation of water from its porous surface. If a pitcher carries

4 kg

of water and the rate of evaporation is

20 g

per hour, temperature of water in it decreases by

Δ T

in two hours. The value of

Δ T

is close to (ratio of latent heat of evaporation to specific heat of water is

540 ° C

)

EASY

Physics>Heat and Thermodynamics>Thermal Properties of Matter>Change of State

The quantities of heat required to raise the temperature of two solid copper spheres of radii

r_{1}

and

r_{2} (r_{1} = 1.5 r_{2})

through

1 K

are in the ratio:

EASY

Physics>Heat and Thermodynamics>Thermal Properties of Matter>Change of State

Latent heat of vaporisation of water is

22.6 \times 10^{5} J {kg}^{- 1}

. The amount of heat needed to convert

100 kg

of water into vapour at

100 ° C

EASY

Physics>Heat and Thermodynamics>Thermal Properties of Matter>Change of State

A closed bottle containing water at

30^{o} C

is open on the surface of the moon. Then-

EASY

Physics>Heat and Thermodynamics>Thermal Properties of Matter>Change of State

Two systems are in thermal equilibrium. The quantity which is common for them is

Observe the following temperature Vs. time graph and fill in the blank: During transition of solid phase to liquid, the object absorbs (electric \chemical \heat) energy, but its temperature does not increase.

Important Questions on Thermal Properties of Matter

Learn and Prepare for any exam you want !

Observe the following temperature Vs. time graph and fill in the blank:

During transition of solid phase to liquid, the object absorbs (electric \chemical \heat) energy, but its temperature does not increase.