A body of mass $(4m)$ is lying in $x-y$ plane at rest. It suddenly explodes into three pieces. Two pieces, each of mass $(m)$ move perpendicular to each other with equal speeds $(v).$ The total kinetic energy generated due to explosion is................. $mv^2$
$0$
$1.5$
$2$
$4$
Two particles having masses $4\, g$ and $16\, g$ respectively are moving with equal kinetic energies. The ratio of the magnitudes of their linear momentum is $n : 2 .$ The value of $n$ will be ...... .
A bomb of mass $9\,kg$ explodes into $2$ pieces of mass $3\,kg$ and $6\,kg.$ The velocity of mass $3\,kg$ is $1.6\, m/s$, the K.E. of mass $6\,kg$ is ............ $J$
The kinetic energy of a body decreases by $36\%$. The decrease in its momentum is ............... $\%$
A ball is thrown up with a certain velocity at an angle $\theta$ to the horizontal. The kinetic energy $KE$ of the ball varies with horizontal displacement $x$ as
A rifle bullet loses $1/20th$ of its velocity in passing through a plank. The least number of such planks required just to stop the bullet is