Question

A lead bullet of a specific heat 's' moving with a velocity v strikes a wall and stops. If half of its energy is converted into heat, the rise in its temp. will be :

Answer 1

$$\begin{gathered} Enegryofthebulletwhenbullethitsthewall=\frac{1}{2}m{v}^2 \\ Heatenergy=\frac{Energy}{2}=\frac{1}{4}m{v}^2 \\ Heatenergy=ms∆T \\ where∆Tisthechangeintempotriseintemp. \\ ms∆T=\frac{1}{4}m{v}^2 \\ ∆T=\frac{v^2}{4s} \end{gathered}$$