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Read the following statements: A. When small temperature difference between a liquid and its surrounding is doubled, the rate of loss of heat of the liquid becomes twice. B. Two bodies P and Q having equal surface areas are maintained at temperature 10°C and 20°C. The thermal radiation emitted in a given time by P and Q are in the ratio 1 : 1.15. C. A Carnot Engine working between 100 K and 400 K has an efficiency of 75%. D. When small temperature difference between a liquid and its surrounding is quadrupled, the rate of loss of heat of the liquid becomes twice. Choose the correct answer from the options given below

1. A, B, C only
2. A, B only
3. A, C only
4. B, C, D only

Correct answer: A, B only

Solution

Statements A and B are correct because A accurately describes the relationship between temperature difference and heat loss, while B correctly reflects the proportionality of thermal radiation emitted by bodies at different temperatures. Statement C is incorrect as the efficiency of a Carnot engine is calculated using the temperatures in Kelvin, and statement D misrepresents the relationship between temperature difference and heat loss.

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