A bob of mass ' $m$ ' is suspended by a light string of length ' $L$ '. It is imparted a minimum horizontal velocity at the lowest point $A$ such that it just completes half circle reaching the top most position B. The ratio of kinetic energies $\frac{(\text { K.E. })_A}{(\text { K.E. })_B}$ is:

A ring of radius $4a$ is rigidly fixed in vertical position on a table. A small disc of mass $m$ and radius $a$ is released as shown in the fig. When the disc rolls down, without slipping, to the lowest point of the ring, then its speed will be

$A$ small cube with mass $M$ starts at rest at point $1$ at a height $4R$, where $R$ is the radius of the circular part of the track. The cube slides down the frictionless track and around the loop. The force that the track exerts on the cube at point $2$ is nearly ……… times the cube's weight $mg$.

A bottle of sodawater is grasped by the neck and swing briskly in a vertical circle. Near which portion of the bottle do the bubbles collect

The maximum velocity at the lowest point, so that the string just slack at the highest point in a vertical circle of radius $l$