Question #e5ff1

1 Answer
Apr 7, 2016

Answer:

At the bottom

Explanation:

For the body to continue with circular motion, a centripetal force is required. If we assume the body moves at the same speed, then the centripetal force will be constant #F_c=mv^2/r#

If we define T as the tension and mg as the object's weight

At the bottom:
#T_b-mg = F_c# .
Tension always acts towards the centre. The tension net of the weight has to provide the centripetal force. This can rearranged as:

#T_b= F_c+mg#

At the top:
#T_t+mg= F_c#. The tension and the weight provide centripetal force, which is the same as:

#T_t=F_c-mg#

And at middle:
#T_m=F_c# (weight acts perpendicular to tension and centripetal force, so affects neither)

Hence if #F_c# is constant, then the tension is greatest at the bottom.