Heat required to melt 1,gm of ice is 80, cal . A man melts 60, gm of ice by chewing it in one minute

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10-1.Thermometry, Thermal Expansion and Calorimetry

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Heat required to melt $1\,gm$ of ice is $80\, cal$. A man melts $60\, gm$ of ice by chewing it in one minute, his power is ........ $W$

A

$4000$

B

$336$

C

$1.33$

D

$0.75$

Solution

Total heat $=\mathrm{ML}=(60 \mathrm{gm} \times 80 \mathrm{cal} / \mathrm{gm}) \times 4.2 \mathrm{J}$

Power $=\frac{\text { Total Energy }}{\text { time }}=\frac{60 \times 80 \times 4.2}{60 \mathrm{sec}} \mathrm{J}=336 \mathrm{W}$

Standard 11

Physics

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