A ball of mass $2\;kg$ and another of mass $4\; kg$ are dropped together from a $60$ feet tall building. After a fall of $30$ feet each towards earth, their respective kinetic energies will be in the ratio of?
$\sqrt 2 \,\,:\,\,1$
$1 : 4$
$1 : 2$
$1\,\,:\,\,\sqrt 2 $
A ball is projected from ground at an angle of $\theta $ from horizontal then graph of kinetic energy and time will be
A shell of mass $200\, gm$ is ejected from a gun of mass $4\, kg$ by an explosion that generates $1.05\, kJ$ of energy. The initial velocity of the shell is .............. $\mathrm{ms}^{-1}$
Two bodies of masses $2m$ and $m$ have their K.E. in the ratio $8 : 1$, then their ratio of momenta is
Sand is deposited at a uniform rate of $20\ kg/s$ and with negligible kinetic energy on an empty conveyor belt moving horizontally at a constant speed of $10$ meters per minute. Find the force required to maintain constant velocity of the conveyor belt.
Two bodies of different masses ${m_1}$ and ${m_2}$ have equal momenta. Their kinetic energies ${E_1}$ and ${E_2}$ are in the ratio