Question

A man needs 40 sec. in complcting 1 revolution in a circular field of diameter
200 metre. If he runs in the same circular path for 2 minutes 20 sec., then calculate
the total distance and
displacement from the starting point that man covered​

Answer 1

Explanation:

The total distance after 2min 20sec =

Distance covered in 40 sec= 2πr

$2\pi \: r \\ 2\pi \: \frac{d}{2 } \\ 2\pi \: \frac{200}{2 } \\ 2\pi100 \\ 200\pi$

Distance covered in 40 sec=200π

Distance covered in 1 sec=

$\frac{200\pi}{40} \\ = 5\pi$

Distance covered in 80sec=

$5\pi \times 80 = 400\pi$

Displacement= 0 because it only depend upon initial and final point.