question_answer

A bullet moving with a speed 350 m/s enters a concrete wall and penetrates a distance of 5.0 m before coming to rest. Find the retardation of the bullet.

Answer:

\[u=350m/s.\] \[s=50cm=0.05m\] \[v=0\] Retardation (– a) = ? We know, \[a=\frac{{{v}^{2}}-{{u}^{2}}}{2s}=\frac{0-{{(350)}^{2}}}{2\times 0.05}\] \[=\frac{350\times 350}{0.1}=12.25\times {{10}^{5}}m/{{s}^{2}}\]