Mass $m$ is released from point $A$ as shown in figure then tension in the string at the point $B$ will be
$mg$
$2mg$
$3mg$
$4mg$
A particle of mass $m$ strikes a wall with speed $v$ at an angle $30^{\circ}$ with the wall elastically as shown in the figure. The magnitude of impulse imparted to the ball by the wall is
A bomb of mass $1 \,kg$ initially at rest, explodes and breaks into three fragments of masses in the ratio $1: 1: 3$. The two pieces of equal mass fly off perpendicular to each other with a speed $15 \,m / s$ each. The speed of heavier fragment is ........... $m / s$
If $n$ balls hit elastically and normally on a surface per unit time and all balls of mass $m$ are moving with same velocity $u$, then force on surface is ..........
A block of mass $m$ is released on a smooth inclined plarie of inclination $\theta$ with the horizontal. The force exerted by the plane on the block has a magnitude
Two blocks are connected by a spring. The combination is suspended, at rest, from a string attatched to the ceiling, as shown in the figure. The string breaks suddenly. Immediately after the string breaks, what is the initial downward acceleration of the upper block of mass $2\,m$ ?