Question

A lead bullet moves horizontally with velocity of 130 m-s^-1 and embedded into a cement wall after collision. If the specific heat capacity of lead =130J. Kg^-1.°c^-1 and all the heat produced is absorbed by the bullet what is the increase in temperature of the bullet?

Answer 1

Kinetic energy of the bullet

$$E_K=\frac12 mv^2$$

fully converts into heat:

$$E_K=E_H=cm\Delta t,\\\space\\ \Delta t=\frac{E_K}{cm}=\frac{v^2}{2c}=65º\text{C}.$$