Questions & Answers

Question

Answers

A.$\pi $ rad/sec.

B.$2\pi $ rad/sec.

C.$4\pi $ rad/sec.

D.$4{\pi ^2}$ rad/sec.

Answer
Verified

Formula Used: Angular speed $\omega {\text{ = 2}} \times \pi \times \eta $ rad/sec.

Where $\eta $ is the frequency of the wheel.

Fly wheel makes$120$ revolutions per minute which is the frequency of the wheel ($\eta $).

So revolutions made by wheel per second ($\eta $)= $\dfrac{{120}}{{60}}$ =$2$

Now, the angular speed of the wheel is radian per second.

$\omega {\text{ = 2}} \times \pi \times \eta $

$\omega {\text{ = 2}} \times \pi \times 2$

$\omega {\text{ = 4}}\pi $

The angular speed of the wheel is $4\pi $ rad/sec.