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प्रश्न
Describe a method to determine the specific heat capacity of a solid (say, a piece of copper).
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उत्तर
First we weigh the given piece of solid and note its mass m1. Then it is heated by suspending it inside a heater. Then a known mass (say m2) of water is taken in a thin glass beaker and its temperature θ1 is recorded with a thermometer. When the given piece of solid becomes heated, its temperature θ2 is noted and it is quickly dropped into the water contained in the beaker, such that no water splashes out. The contents of beaker are well stirred and the final highest temperature θ3 is noted.
Assuming that the heat capacity of beaker is negligible and there is not heat loss to the surroundings,
Heat lost by the solid = Heat gained by water Mass of solid × Specific heat capacity of solid × Fall in temperature of solid = Mass of water × Sp. capacity of water × Rise in temperature of water.
or m1 × c × (θ2 - θ3) = m3 × 4.2 × (θ3 - θ1)
or c = `("m"_2 xx 4.2 xx (theta_3 - theta_1))/(theta_1 xx (theta_2 - theta_3))` J/g°C
Here we have assumed that specific heat capacity of water is 4.2 J/g°C.
संबंधित प्रश्न
In an experiment on the specific heat of a metal, a 0.20 kg block of the metal at 150 °C is dropped in a copper calorimeter (of water equivalent 0.025 kg) containing 150 cm3 of water at 27 °C. The final temperature is 40 °C. Compute the specific heat of the metal. If heat losses to the surroundings are not negligible, is your answer greater or smaller than the actual value for the specific heat of the metal?
A child running a temperature of 101°F is given an antipyrin (i.e. a medicine that lowers fever) which causes an increase in the rate of evaporation of sweat from his body. If the fever is brought down to 98 °F in 20 min, what is the average rate of extra evaporation caused, by the drug? Assume the evaporation mechanism to be the only way by which heat is lost. The mass of the child is 30 kg. The specific heat of human body is approximately the same as that of water, and latent heat of evaporation of water at that temperature is about 580 cal g–1.
What do you mean by the following statement?
The specific heat capacity of copper is 0. 4 Jg-1 K-1?
The specific heat capacity of water is :
A substance is heated at a constant rate from a low temperature to a high temperature. A graph of temperature against time is shown in the figure. Which part or parts of the graph correspond(s) to the substance existing in two states?

Explain, Why is it advisabile to pour cold water over burns, caused on human body, by hot solids?
Derive an expression for finding out the specific heat capacity of a body (solid) from the readings of an experiment given below:
(i) Mass of empty calorimeter (with stirrer) = m1 gm
(ii) Mass of the metal piece = M gm
(iii) Mass of colorimeter and water = m2 gm
(iv) Initial temperature and water = t1°C
(v) Temperature of hot solid (metal piece) = t2 °C
(vi) Final temperature of the mixture = t°C
(vii) Specific heat of calorimeter = 0.4 J gm / °C
Define specific heat capacity.
