SPECIFIC HEAT OF SOLIDS

 

Principle and Working:
The specific heat capacity of copper, glass and lead are determined by heating the material in a steam chamber and then transferring the heated material into a weighed amount of water in a dewar vessel and measuring the temperature.
In the present setup, the system consists of mixing a given mass m1 of a hot metal specimen with specific heat c1 at temperature T1 and a known mass m2 of water with specific heat c2 at a lower temperature T2 contained in a calorimeter of mass m3with specific heat c3 also initially at temperature T2. Once again we assume the system to be thermally insulated from the surroundings, and the heat capacity of the thermometer, which records the temperature, can be neglected. Let the final temperature of the mixture be Tf . Energy conservation gives:

Qlost(Metal) = Qgained(Water) + Qgained(Calorimeter)

m1c1(T1 - Tf) =m2c2(Tf -T2) +m3c3(Tf-T2) which,

yields the unknown specific heat c1 of the metal specimen as

c1 = (m2c2 +m3c3)( Tf -T2)/m1(T1 -Tf)

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