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.
- ABoth A and R are individually true and R is the correct explanation of A
- BBoth A and R are individually true but R is NOT a correct explanation of ACorrect
- CA is true but R is false
- DA is false but R is true
Explanation
The assertion is true because copper is a much better conductor of heat than glass. When you touch both materials at the same high temperature, copper transfers heat to your hand much faster than glass does, making it feel hotter.
The reason is also factually true as the density of copper (approximately 8.9 g/cm³) is indeed higher than that of glass (approximately 2.5 g/cm³). However, density is not the property that determines how hot an object feels when touched. Thermal conductivity is the property responsible for this sensation. Therefore, while both the assertion and the reason are individually true, the reason is not the correct explanation for the assertion.
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