Question

A small body of mass m = 0.1 kg at the end of a cord 1 m long swings in a vertical circle. Its speed is 2 mIs when the cord makes an angle θ = 30° with the vertical. Find the tension in the cord.

Answer 1

Data: m = 0.1 kg, r = 1 m, y = 2 m/s, θ = 30°, g = 9.8 m/s²

When the cord makes an angle θ with the vertical, the centripetal force on the body is

\(\frac{mv^2}r\) = T - mg cos \(\theta\)

The tension in the cord,

T = \(\frac{mv^2}r\) + mg  cos \(\theta\)