Question

A 100 g of iron nail is hit by a $1.5$ $kg$ hammer striking at a velocity of $60 \;ms^{–1}$. What will be the rise in the temperature of the nail if one fourth of energy of the hammer goes into heating the nail?
[Specific heat capacity of iron = $0.42\; Jg^{–1} °C^{–1}$]

• A. 675°C
• B. 1600°C
• C. 16.07°C
• D. 6.75°C

Answer 1

Answer: (C)

16.07°C

Answer 2

$\frac{1}{2} \times 1.5 \times 60^2 \times \frac{1}{4} = 100 \times 0.42 \times \triangle \;T$

$\triangle\; T = \frac{1.5\times 60^2}{8\times 100 \times 0.42} = 16.07 \;\degree C$