A particle of mass $m$ moving in the $x$ direction with speed $2 v$ is hit by another particle of mass $2 m$ moving in the $y$ direction with speed $v$. If the collision is perfectly inelastic, the percentage loss in the energy during the collision is close to $..........\%$
$56$
$62$
$44$
$50$
Select the false statement
A mass of $20\, kg$ moving with a speed of $10\,m/s$ collides with another stationary mass of $5\,kg.$ As a result of the collision, the two masses stick together. The kinetic energy of the composite mass will be ............. $J$
A body falling from a height of $10\,m$ rebounds from hard floor. If it loses $20\%$ energy on the impact, then coefficient of restitution is
An alpha-particle of mass $m$ suffers $1-$ dimensional elastic collision with a nucleus at rest of unknown mass. It is scattered directly backwards losing, $64\%$ of its initial kinetic energy. The mass of the nucleus is .......... $\mathrm{m}$
A small particle elastically strikes a fixed smooth sphere of $4\,cm$ radius, with a speed of $5\,m/s$. The impact parameter for the collision is $2\sqrt {3\,} \,cm$ . Calculate the angle of deflection of the particle ............... $^o$