A gun fires a lead bullet of temperature 300 K into a wooden block. The bullet having melting temperature of 600 K penetrates into the block and melts down. If the total heat required for the process is 625 J, then the mass of the bullet is ________ grams.
(Latent heat of fusion of lead $=2.5 \times 10^4 \mathrm{JKg}^{-1}$ and specific heat capacity of lead $=125 \mathrm{JKg}^{-1}$ $\left.\mathrm{K}^{-1}\right)$

Question

Aicharya · Accepted Answer

$\begin{aligned} & 625=\mathrm{ms} \Delta \mathrm{T}+\mathrm{mL} \ & 625=\mathrm{m}\left[125 	imes 300+2.5 	imes 10^4ight] \ & 625=\mathrm{m}[37500+25000] \ & 625=\mathrm{m}[62500] \ & \mathrm{m}=\frac{1}{100} \mathrm{~kg} \ & \mathrm{M}=10 	ext { grams }\end{aligned}$

A gun fires a lead bullet of temperature 300 K into a wooden block. The bullet having melting temperature of…

Solution