Assertion (A) : A piece of copper and a piece of glass are heated to the same temperature. When touched,

Monjur Alahi

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. 

Codes: 

(a) Both A and R are true and R is the correct explanation of A 

(b) Both A and R are true but R is not a correct explanation of A 

(c) A is true but R is false 

(d) A is false but R is true


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Salim Ahmed Kawsar

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(b) Both statement 1 and statement 2 are correct. On heating up to same temperature copper piece is found hotter than in comparison to glass piece because copper being a metal is a good conductor of heat and electricity while glass on the other hand is a poor conductor of heat. The density of copper is 8.92 gm/ cm3 and of glass is 2.6 gm/cm3 .

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