Question

circular track of radius 20 metre and runner cover in one revolution then find its speed if time taken by 10 seconds

Answer 1

Answer: speed=distance/time

Distance =2πr=2×π20=40π

Time taken=10sec

Speed=40π/10=4π=4×22/7=12.56m/s

Explanation:

Answer 2

V= w×r

V=linear velocity

W=angular velocity

r=radius of circle

Now, w=angular displacement/time

Here one revolution means 2pie angular displacement.

So,w=2 pie/10=pie/5 rad/a

V=pie/5 ×20=4 pie = 4×3.14= 12.56m/s

Pls feel free to ask more doubts.