Question

A bullet of mass 50 g travelling it 500 m/s penetrates 100 cm into a wooden block. The average force exerted on the block is

• A. $ 6.25\times {{10}^{5}}N $
• B. $ 26.5\times {{10}^{4}}N $
• C. $ 6.25\times {{10}^{3}}N $
• D. $ 2.65\times {{10}^{4}}N $

Answer 1

Answer: (C)

From the relation $ Fs=\frac{1}{2}m{{v}^{2}}-\frac{1}{2}m{{u}^{2}} $ $ \therefore $ $ -F(1)=\frac{1}{2}\left( \frac{50}{1000} \right)[{{(0)}^{2}}-{{(500)}^{2}}] $ $ -F=-\frac{25}{1000}\times 500\times 500 $ $ F=6.25\times {{10}^{3}}N $