Question

Starting from rest, a fan takes ten seconds to attain the maximum speed of $600rpm$ (revolutions per minute). Assuming constant acceleration, find the time taken by the fan in attaining half the maximum speed.

Answer 1

$w=\alpha t$

$\Rightarrow \frac{600}{60}=\alpha 10$

$\alpha =1$

$w=\alpha t$

$\Rightarrow \frac{300}{2\times 60}=1\times t=2.5sec$

Hence, the answer is $2.5sec.$