Question

A wheel accelerates uniformly from rest to a rotational speed of 10 rad/s in 5 s. What is its angular acceleration?

Answer 1

Answer:

angular acceleration=$2 \frac{rad}{s^{2} }$

Explanation:

Kinematic equation for uniformly accelerated circular motion:

$wf=wi+\alpha *t$

wf=final angular speed $(\frac{rad}{s} )$

wi=initial angular speed $(\frac{rad}{s} )$

$\alpha$= angular acceleration $(\frac{rad}{s^{2} } )$

We replace wf=10$\frac{rad}{s}$,wi=0, t=5s in the equation(1):

$10=0+\alpha *5$

$\alpha =\frac{10}{5}$

$\alpha =2 \frac{rad}{s^{2} }$

The angular acceleration is 2 $\frac{rad}{s^{2} }$