What force should be applied on the wedge so that block over it does not move? (All surfaces are smooth)

In the arrangement as shown, tension $T_2$ is $\left(g=10 \mathrm{m} {\mathrm{s}}^{-2}\right)$

In the figure, a ball of mass $m$ is tied with two strings of equal length as shown. If the rod is rotated with angular velocity $\omega$, then

A particle describes a horizontal circle of radius $r$ on the smooth surface of an inverted cone as shown. The height of plane of circle above vertex is $h.$ The speed of particle should be

A particle of mass $m$ moves with constant speed $v$ on a circular path of radius $r$ as shown in figure. The average force on it during its motion from $A$ to $B$ is