Assertion (A) >: A piece of copper and a piece of glass are heated to the same temperature. When touched, thereafter, the copper piece appears hotter than the glass piece. Reason (R) >: The density of copper is more than that of glass.

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Q: 102 (IAS/2001)

Assertion (A): A piece of copper and a piece of glass are heated to the same temperature. When touched, thereafter, the copper piece appears hotter than the glass piece.
Reason (R): The density of copper is more than that of glass.

question_subject: 

Science

question_exam: 

IAS

stats: 

0,33,63,40,33,20,3

keywords: 

{'copper': [1, 0, 1, 1], 'copper piece': [0, 0, 1, 0], 'glass': [0, 0, 1, 4], 'glass piece': [0, 0, 1, 0], 'density': [2, 0, 1, 3], 'same temperature': [0, 1, 0, 1]}

The correct answer is option 2 - Both A (Assertion) and R (Reason) are individually true, but R is not the correct explanation of A.

Looking at the statement A, it is correct to say that when a piece of copper and a piece of glass are heated to the same temperature, the copper piece will feel hotter than the glass piece when touched. This happens because copper is a good conductor of heat while glass is not.

Statement R is also true - the density of copper is indeed more than glass. However, this fact does not explain why copper feels hotter than glass at the same temperature. The phenomenon of feeling copper hotter is related to their heat conduction properties and not to density which is indicated in statement R. Hence, R is not a correct explanation for A, making option 2 the correct answer.