A body of $\mathrm{m} \mathrm{kg}$ slides from rest along the curve of vertical circle from point $A$ to $B$ in friction less path. The velocity of the body at $B$ is:
(given, $\mathrm{R}=14 \mathrm{~m}, \mathrm{~g}=10 \mathrm{~m} / \mathrm{s}^2$ and $\sqrt{2}=1.4$ )
$19.8 \mathrm{~m} / \mathrm{s}$
$21.9 \mathrm{~m} / \mathrm{s}$
$16.7 \mathrm{~m} / \mathrm{s}$
$10.6 \mathrm{~m} / \mathrm{s}$
A particle is projected vertically upwards with a speed of $16\ m/s$ , after some time , when it again passes through the point of projection, its speed is found to be $8\ m/s$ . It is known that the work done by air resistance is same during upward and downward motion. Then the maximum height attained by the particle is ...................... $\mathrm{m}$ ( $g$ = $10\ m/s^2$ )
The area of the acceleration-displacement curve of a body gives
A ball of mass $m$ moves with speed $v$ and strikes a wall having infinite mass and it returns with same speed then the work done by the ball on the wall is
By what reasons chemical energy produced in chemical process ?
In a ballistics demonstration a police officer fires a bullet of mass $50.0 \;g$ with speed $200 \;m s ^{-1}$ on soft plywood of thickness $2.00 \;cm .$ The bullet emerges with only $10 \%$ of its initial kinetic energy. What is the emergent speed of the bullet?