A wire, which passes through the hole is a small bead, is bent in the form of quarter of a circle. The wire is fixed vertically on ground as shown in the figure. The bead is released from near the top of the wire and it slides along the wire without friction. As the bead moves from $A$ to $B$, the force it applies on the wire is
always radially outwards
always radially inwards
radially outwards initially and radially inwards later.
radially inwards initially and radially outwards later.
A ball is thrown from $10\,m$ height at speed $v_0$ vertically downward. In colliding surface of earth it looses $50\%$ of its energy and again reach upto same height. Value of $v_0$ is :- .................$\mathrm{m}/ \mathrm{s}$
A bomb is projected upwards. At topmost point it explodes in three identical fragments. First fragment comes to ground in $10\ sec$. and others in $20\ sec$ each. Then the height reached by the original bomb is.........$m$
Write the principle of conservation of mechanical energy for non-conservative force.
As per the given figure, two blocks each of mass $250\,g$ are connected to a spring of spring constant $2\,Nm ^{-1}$. If both are given velocity $V$ in opposite directions, then maximum elongation of the spring is:
In an elastic collision of two billiard balls, which of the following quantities remain conserved during the short time of collision of the balls ? (i.e. when they are in contact)
$(a)$ Kinetic energy.
$(b)$ Total linear momentum.
Give reason for your answer in each case.