Question

An object of mass 2 kg attached to a wire of length 5m is revolved in a horizontal circle. If it makes 60 r.p.m then find the tension in the string.

Answer 1

Mass, $m=2$ $kg$

Radius, $r=5$ $m$

Angular speed, $\omega =60$ $rpm$

$⟹\omega =\frac{60}{60}$

$⟹\omega =1$ $rps$

$⟹\omega =1\times 2\pi$

$⟹\omega =2\pi$ $rad/s$

Tension, $T=mr{\omega }^2$

$⟹T=2\times 5\times 4{\pi }^2$

$⟹T=394.78$ $N$