Q4 of 15 Page 103

Solve the following examples.

Two substances A and B have specific heats c and 2 c respectively. If A and B are given Q and 4Q amounts of heat respectively, the change in their temperatures is the same. If the mass of A is m, what is the mass of B?

Given data:


● Specific heat of substance A = c


● Specific heat of substance B = 2c


● Heat was given to substance A = Q


● Heat was given to substance A = 4Q


● Mass of A = m


Calculation:


The formula to calculate the heat energy given to body A is as follows.


Q = m×c×∆T …………. (1)


The formula to calculate the heat energy given to body B is as follows.


4Q = mB×2c×∆T ……………. (2)


Divide equation (2) by equation (1).



or



or


mB = 2m


The mass of substance B is 2m.


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