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प्रश्न
Study the following procedure and answer the questions below:
1. Take 3 spheres of iron, copper and lead of equal mass.
2. Put all the 3 spheres in boiling water in a beaker for some time.
3. Take 3 spheres out of the water. Put them immediately on a thick slab of wax.
4. Note, the depth that each sphere goes into the wax.
i) Which property of substance can be studied with this procedure?
ii) Describe that property in minimum words.
iii) Explain the rule of heat exchange with this property.
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उत्तर
i. Specific heat
ii. Specific heat : The amount of heat energy required to raise the temperature of a unit mass of an object by 1oC .
iii. According to the principle of hear exchange :
Heat energy lost by the hot object = Heat energy gained by the cold
object
In this activity heat absorbed by iron sphere is transmitted more in the wax, hence sphere goes deepest in to wax, while lead sphere absorbs less heat, resulting in less transmission of heat in the wax hence sphere goes the least depth in the wax.
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