JEE Main2017PhysicsThermal Properties of MatterActual
A copper ball of mass 100   g is at a temperature T . It is dropped in a copper calorimeter of mass 100   g, filled with 170   g of water at room temperature. Subsequently, the temperature of the system is found to be 75 ° C . T is given by: (Given: room temperature = 30 ° C , specific heat of copper = 0.1   cal g - 1 ° C - 1 )
Options
- A825 ° C
- B800 ° C
- C885 ° C
- D1250 ° C
Correct answer
C. 885 ° C
Step-by-step solution
m c b = 100   g ,   T o C m c = 100   g ,   30 o C m w = 170   g ,   30 o C Net heat loss = Net heat gain ⇒ 100 × 0.1 × T - 75 = 100 × 0.1 × 75 - 30 + 170 × 1 × 75 - 30 ⇒ T - 75 = 45 + 17 × 45 ⇒ T = 885 ° C .