Question

A shell of mass 200 g is ejected from a gun of mass 4 kg by an explosion that generates 1.05 kJ of energy. The velocity of the shell is

• A. 102 $m{s}^{-1}$
• B. 82 $m{s}^{-1}$
• C. 41 $m{s}^{-1}$
• D. 120 $m{s}^{-1}$

Answer 1

The correct option is A 102 $m{s}^{-1}$

The mass is $m=0.2Kg$ and energy is $E=1.05kJ=1.05\times 1000J$

Whole energy of the explosion will be $delivered$ to the $shell$ in form of kinetic energy so if the velocity be $v$ then

$\frac{m{v}^2}{2}=1.05\times 1000J$

so $v=\sqrt{\frac{1050\times 2}{0.2}}=102.46m/s$