Question

Certain amount of heat is given to 100 g of copper to increase its temperature by 21 $^{\circ}$C. if the same amount of heat is given to 50 g of water, then the rise in its temperature is (specific heat capacity of copper = 400 Jkg$^{-1} K^{-1}$ and that for water =4200Jkg$^{-1}ZK^{-1}$

• A. 4$^{\circ}$C
• B. 5.25$^{\circ}$C
• C. 8$^{\circ}$C
• D. 6$^{\circ}$C
• E. 10.5$^{\circ}$C

Answer 1

Answer: (A)

The amount of heat supplied is given by the
relation $ \, \, \, \, \, Q=mc \Delta T$
Here , m = 100g = 0. 1 kg,c = 400J/ kg -K
$\, \, \, \, \, \, \, \, \Delta T =21 K \, for \, copper$
$Thus , \, \, \, \, \, \, \, \, Q = 0.1 \times 400 \times 21 = 840J$
Hence , $ \, \, \, \, \, 840=0.05 \times 4200 \times \Delta T$
$\Rightarrow \, \, \, \, \, \, \, \, \, \, \Delta T =4^{\circ}C$