Question

An object rotates by an angle of 90 degrees in 4 secs. Find the angular displacement in radians

• A. $\frac{\pi }{2}$ radians
• B. $\frac{\pi }{4}$ radians
• C. $\frac{2}{\pi }$ radians
• D. $\pi$ radians

Answer 1

The correct option is A $\frac{\pi }{2}$ radians

$\pi$ radians = $180$ degrees
Hence 90 degrees = $\frac{\pi }{180}.\left(90\right)=\frac{\pi }{2}$ radians