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A copper ball of mass 100 gm is at a temperature T. It is dropped in a copper calorimeter of mass 100 gm, filled with 170 gm 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/gm°C)

1. 800°C
2. 885°C
3. 1250°C
4. 825°C

Correct answer: 885°C

Solution

The correct option is derived from the principle of conservation of energy, where the heat lost by the copper ball equals the heat gained by the water and the calorimeter. By applying the formula for heat transfer and solving for the initial temperature T, we find that it must be 885°C to achieve the final equilibrium temperature of 75°C.

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