Question

A bullet of mass 10 g leaves a riffle at an initial velocity of 1000 m/sec and strikes the earth at the same level with a velocity of 500 m/sec, The work in overcoming the resistance of air will be:

• A. 500 J
• B. 5000 J
• C. 3750 J
• D. 475 J

Answer 1

The correct option is C 3750 J

The work done is loss in KE.
$W=1/2\times 0.01\times ({1000}^2-{500}^2)=15\times 250=3750J$
$\therefore W=3750J$