## Question

### Solution

Correct option is

MLT– 3 K– 1

For a bar of cross-sectional area A, length l and having temperatures  at its two ends, the amount of heat energy Q flowing normally across the  bar in time  is given by

Where k is the coefficient of thermal conductivity. Therefore,

#### SIMILAR QUESTIONS

Q1

Two rods of different materials having coefficient of thermal expansion  and Young’s modulii Y1 and Y2 are fixed between two rigid and massive walls. The rods are heated to the same temperature. If there is no bending of the rods, the thermal stresses developed in them are equal provided

Q2

300 g of water at 25oC is added to 100 g of ice at 0oC. The final temperature of the mixture is

Q3

100 g of ice at 0oC is mixed with 100 g of water 80oC. The final temperature of the mixture will be

Q4

Steam at 100oC is passed into 1.1 kg of water contained in a calorimeter of water equivalent 0.02 kg at 15oC till the temperature of the calorimeter rises to 80oC. The mass of steam condensed in kilogram is

Q5

If there are no heat losses, the heat released by the condensation of xgrams of steam at 100oC into water 100oC converts y grams of ice at 0oC into water at 100oC. The ratio y/is nearly

Q6

One mole of oxygen is heated from 0oC, at constant pressure, till its volume increases by 10%. The specific heat of oxygen, under these conditions is 0.22 cal g – 1 K – 1. The amount of heat required (in joules) is

Q7

A drilling machine of power P watts is used to drill a hole in copper block of mass M kg. If the specific heat of a copper is s J  and 40% of  the power is lost due to heating of the machine, the rise in the temperature of the block in T seconds will be (in oC)

Q8

A geyser, operating on LPG (liquefied petroleum gas) heats water flowing at the rate of 3.0 litres per minute, from 27oC to 77oC. If the heat of combustion of LPG is , how much fuel in grams is consumed per minute?

Q9

A copper block of mass 2 kg is heated to a temperature of 500oC and then placed in a large block of ice at 0oC. What is the maximum amount of ice that can melt? The specific heat of copper is 400 j  and latent heat of fusion of water is .

Q10

Two different metal rods of the same length have their ends kept at the same temperatures and  with . If A and are their cross-sectional areas and k1 and k2 their thermal conductivities, the rate of flow of heat in the two rods will be the same if