MEDIUM

11th ICSE

IMPORTANT

Earn 100

The opposite faces of an iron cube are in steam $(100 ° C)$ and in ice $(0 ° C)$ . Each side of the cube is $2 cm$ and the thermal conductivity of iron is $0.2 cal s^{- 1} {cm}^{- 1} ° C^{- 1}$ . How much ice will melt in $5 minutes$ ? Latent heat of ice is $80 cal g^{- 1}$ .

Important Questions on Thermal Conduction

HARD

11th ICSE

IMPORTANT

ISC Physics Class XI Part 1>Chapter 24 - Thermal Conduction>NUMERICALS>Q 8

Two vessels of different materials are identical in size and wall-thickness. They are filled with equal quantities of ice at

0 ° C

. If the ice melts completely in

10

and

25

minutes respectively then compare the coefficients of thermal conductivity of the materials of the vessels.

HARD

11th ICSE

IMPORTANT

ISC Physics Class XI Part 1>Chapter 24 - Thermal Conduction>NUMERICALS>Q 9

One end of a

25 cm

long metal bar is in steam and the other is in contact with ice. If

12 gm

of ice melts per minute, what is the thermal conductivity of the metal? Cross-section of the bar is

5 {cm}^{2}

and latent heat of ice is

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

HARD

11th ICSE

IMPORTANT

ISC Physics Class XI Part 1>Chapter 24 - Thermal Conduction>NUMERICALS>Q 10

An iron boiler is

1 cm

thick and has a heating area of

2 m^{2}

. The two surfaces of the boiler are at

234 ° C

and

100 ° C

respectively. If, the latent heat of steam is

536 kcal {kg}^{- 1}

and thermal conductivity of iron is

1.6 \times 10^{- 2} kcal s^{- 1} m^{- 1} ° C^{- 1}

, then how much water will be evaporated into steam per minute?

HARD

11th ICSE

IMPORTANT

ISC Physics Class XI Part 1>Chapter 24 - Thermal Conduction>NUMERICALS>Q 11

Two rods of same metal and of same cross-section have lengths

0.5 m

and

0.8 m

. The temperature difference across the ends of the first rod is

40 ° C

. Find the temperature difference across the second rod, if the rate of heat conduction is equal in both the rods.

EASY

11th ICSE

IMPORTANT

ISC Physics Class XI Part 1>Chapter 24 - Thermal Conduction>NUMERICALS>Q 12

The temperature difference between the two ends of a bar

1.0 m

long is

50 ° C

and that for the other bar

1.25 m

long

75 ° C

. Both the bars have same area of cross-section. If the rates of conduction of heat in the two bars are the same, find the ratio of the coefficients of thermal conductivity of the materials of the two bars. If both the bars are of same metal, find the ratio of the rates of heat conduction in them.

EASY

11th ICSE

IMPORTANT

ISC Physics Class XI Part 1>Chapter 24 - Thermal Conduction>NUMERICALS>Q 13

Three thermometers

A

B

and

C

read respectively

36 ° C

32 ° C

and

27 ° C

A

lies between the body and vest of a man,

B

between vest and the shirt and

C

between the shirt and the coat. If the vest and the shirt are equally thick, calculate the ratio of their thermal conductivities.

MEDIUM

11th ICSE

IMPORTANT

ISC Physics Class XI Part 1>Chapter 24 - Thermal Conduction>NUMERICALS>Q 14

The ratio of the areas of cross-section of two rods of different materials is

1 : 2

and the ratio of the thermal conductivities of their materials is

4 : 3

. On keeping equal temperature-difference between the ends of these rods, the rate of conduction of heat are equal. Determine the ratio of the lengths of the rods.

MEDIUM

11th ICSE

IMPORTANT

ISC Physics Class XI Part 1>Chapter 24 - Thermal Conduction>NUMERICALS>Q 15

Two vessels of different materials are identical in size and shape. Both are filled with equal masses of boiled water and are placed on the same heater. If thermal conductivities of the metals of the vessels be

5 \times 10^{- 2}

and

3 \times 10^{- 2} k c a l s^{- 1} m^{- 1} ° C^{- 1}

respectively, then calculate the ratio of the timings taken by the water in the vessels to convert into steam.

The opposite faces of an iron cube are in steam 100°C and in ice 0°C. Each side of the cube is 2 cm and the thermal conductivity of iron is 0.2 cal s-1 cm-1 °C-1. How much ice will melt in 5 minutes? Latent heat of ice is 80 cal g-1.

Important Questions on Thermal Conduction

Learn and Prepare for any exam you want !

The opposite faces of an iron cube are in steam $(100 ° C)$ and in ice $(0 ° C)$ . Each side of the cube is $2 cm$ and the thermal conductivity of iron is $0.2 cal s^{- 1} {cm}^{- 1} ° C^{- 1}$ . How much ice will melt in $5 minutes$ ? Latent heat of ice is $80 cal g^{- 1}$ .