In the case of a whirling , a force is needed if
(i) the v of the ball is
(ii) the r of the circle is
(iii) the m of the ball is

In the case of a whirling ball, , when m is , v is , and r is the .

The which acts towards the and keeps a body moving in a path is called the .

In the case of a whirling ball, if the force is than the string can bear, the string and the ball off with speed in a line along the .

When dealing with force, can act as an force.

In the case of a road, the effect of the force N is the force.

In the case of a orbiting the , the force is provided by .

For a circular orbit, the orbital period .