Question

A body rotating with a uniform angular acceleration covers $100\pi$ radians in first 5 s after the start. Find its angular speed at the end of 5 s.

Answer 1

Given, $\theta =100\pi radianst=5s$
From the second equation of angular motion, $\theta =\frac{1}{2}\alpha t^2\Rightarrow 100\pi =\frac{1}{2}\alpha \times 5^2\Rightarrow =8\pi rad/s^2\therefore \omega =\alpha t=8\pi \times 5=40\pi radians$