Question

If a bomb of mass $3mkg$ explodes into two pieces of mass $m$ kg and $2mkg$, the velocity of mass $m$ kg is $16m{s}^{-1}$, then the total kinetic energy released in the explosion will be

• A. $96mJ$
• B. $116mJ$
• C. $192mJ$
• D. $384mJ$

Answer 1

The correct option is C $192mJ$

The velocity of $mkg=16m{s}^{-1}$
and let the velocity of $2mkgmass=v_{2}m{s}^{-1}$
By the law of conservation of momentum
$m\times 16=2m\times v_2$
$v_2=8m{s}^{-1}$
$\therefore$ Kinetic energy of the system
$=\frac{1}{2}m(16{)}^2+\frac{1}{2}(2m\left)\right(8{)}^2=192mJ$.