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Question
Read the following paragraph and answer the questions.
If heat is exchanged between a hot and cold object, the temperature of the cold object goes on increasing due to gain of energy and the temperature of the hot object goes on decreasing due to loss of energy.
The change in temperature continues till the temperatures of both the objects attain the same value. In this process, the cold object gains heat energy and the hot object loses heat energy. If the system of both the objects is isolated from the environment by keeping it inside a heat resistant box (meaning that the energy exchange takes place between the two objects only), then no energy can flow from inside the box or come into the box.
i. Heat is transferred from where to where?
ii. Which principle do we learn about from this process?
iii. How will you state the principle briefly?
iv. Which property of the substance is measured using this principle?
Solution
(i) Heat is transferred from the object at higher temperature to the object at lower temperature.
(ii) We learn the principle of heat exchange from this process.
(iii) Principle of heat exchange states that the heat energy lost by hot object is always equal to heat gained by cold object provided that the system of both the objects is isolated.
(iv) Specific heat of an object can be measured using this principle.
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