Question

A fan blade is initially rotating an angular speed of 4.6 rpm. It slows down and eventually comes to rest in a time of 32 seconds after turning through a total of 8.8 revolutions. Find

a) the angular speed in rad/s

b) the average angular velocity and

c) the average angular acceleration of the fan blade.

Answer 1

$\omega=2\pi\nu=28.9~\frac{rad}s,$

$<\omega>=\frac{\omega+0}2=0.5\omega=14.5~\frac{rad}s,$

$\varepsilon=\frac{\omega^2}{2\varphi}=7.6~\frac{rad}{s^2}.$