Specific Heat Capacity

IMPORTANT

Specific Heat Capacity: Overview

This topic covers concepts, such as, Heat Capacity, Specific Heat Capacity, Molar Specific Heat Capacity, Heat Capacity of Solids, Specific Heat Capacity of Water & Variation of Specific Heat Capacity of Water with Temperature etc.

Important Questions on Specific Heat Capacity

MEDIUM
IMPORTANT

The molar heat capacity of water at constant pressure is  75J K1 mol1. When 1kJ of heat is supplied to 100g of water, which is free to expand, the increase in temperature of water is

                               

EASY
IMPORTANT

A metal cube absorbs 2100.0 J of heat when its temperature is raised by 2 °C. If the specific heat of the metal is 900 J kg-1 K-1, then the mass of the cube is

EASY
IMPORTANT

During an adiabatic process, the pressure of a gas is found to be proportional to the cube of its absolute temperature. The ratio CPCV  for the gas is x2. Find x.

MEDIUM
IMPORTANT

Two different liquids of same mass are kept in two identical vessel, which are placed in a freezer that extracts heat from them at the same rate causing each liquid to transform into a solid. The schematic figure below shows the temperaure T vs time t plot for the two materials. We denote the specific heat in the liquid states to be CL1 and CL2 for materials 1 and 2 respectively, and latent heats of fusion U1 and U2 respectively.

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Choose the correct option.

EASY
IMPORTANT

200 g water is heated from 40 oC to 60 oC . Ignoring the slight expansion of water, the change in its internal energy is close to (Given specific heat of water =4184 J/kg/K):

HARD
IMPORTANT

A current carrying wire heats a metal rod. The wire provides a constant power P to the rod. The metal rod is enclosed in an insulated container. It is observed that the temperature T in the metal rod changes with time t as:

Tt=T01+βt1/4

where β is a constant with appropriate dimension while T0 is a constant with dimension of temperature. The heat capacity of the metal is:

EASY
IMPORTANT

A person weighing 50 kg takes in 1500 kcal diet per day. If this energy were to be used in heating the body of person without any losses, then the rise in his temperature is (specific heat of human body =0.83 cal g-1 -1 )

MEDIUM
IMPORTANT

Amongst object A and B, if the specific heat of object A is less than of object B, then 

MEDIUM
IMPORTANT

A cube of lead of 500 g at 25 °C is supplied with a 3225 J heat. Find the final temperature (in degree Celsius) of the lead cube. (Take, specific heat of lead is 0.129 Jg °C

MEDIUM
IMPORTANT

Calculate the heat energy (in joules) to raise the temperature of 5 kg of water from 20 °C to 100 °C. (Take specific heat of water, sw=4.2×103 J kg-1 K-1)

MEDIUM
IMPORTANT

The amount of heat required to raise the temperature of 1 kg mass of water through 1 K is called its

MEDIUM
IMPORTANT

Specific heat of a substance is given by S=(1+2T) J kg-1 K-1, find out amount of heat required to raise the temperature of 2 kg substance from 10°C to 20°C.

MEDIUM
IMPORTANT

How much heat energy (in kcal) is necessary to raise the temperature of 5 kg of water from 20 to 100?

MEDIUM
IMPORTANT

The number of degrees of freedom of a gas whose specific heat capacity at constant pressure is 33.24 J mol-1 K-1, is
(universal gas constant =8.31 J mol-1 K-1 )

MEDIUM
IMPORTANT

A copper wire 2 m long is stretched by 1 mm. If the energy stored in the stretched wire is converted to heat, calculate the rise in temperature of the wire. (Given: Y=12×1011 dyne cm-2, Density of copper =9 g cm-3 and Specific heat of copper =0.1 calg-1 C-1:

HARD
IMPORTANT

20 gm ice at -10°C is mixed with m gm steam at 100°C. The minimum value of m so that finally all ice and steam converts into water is,

(Use, sice=0.5 cal gm-1 °C, swater=1 cal gm-1 °CL(melting)=80 cal gm-1 and L (vaporization)=540 cal gm-1.)

HARD
IMPORTANT

Which statement is false for specific heat of water?

MEDIUM
IMPORTANT

During illness an 80 kg man ran a fever of 102.2 °F instead of normal body temperature of 98.6 °F. Assuming that the human body is mostly water, how much heat is required to raise his temperature by that amount?

MEDIUM
IMPORTANT

A source of heat supplies heat at a constant rate to a solid cube. The slope of portion CD of the graphs gives :-

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HARD
IMPORTANT

For next 2 question please follow the same

Molar heat capacity of an ideal gas in the process PVx =  constant is given by

              C = R γ - 1 + R 1 - x

An ideal diatomic gas with C V = 5 R 2   occupies a volume V1 at a pressure P1 . The gas undergoes a process in which the pressure is proportional to the volume. At the end of the process the rms speed of the gas molecules has doubled from its initial value.

The molar heat capacity of the gas in the given process is