Question

A body covers a circular pathof radius r in 20 sec.calculate distance and displacement at the end of 70seconds?​

Answer 1

sorry displacement will be 2r and distance will be 7pie r

Answer 2

Given :- A body takes 20 Sec to cover a distance of 2πr units .

The speed will be 2πr/20 = πr/10 m/s

To calculate:- Distance and displacement in 70 seconds.

Solution :-

Distance-> Speed ×Time

-> πr/10 × 70

-> 7πr m

Distance= 7πr m

Displacement->

Here we have to think logically ,

see in 20 seconds the body covers the whole circle i.e. the displacement will be zero , so in 40 seconds it will be zero too ,and in 60 second it will be zero again ...

Then in the remaining 10 seconds the displacement will be ,

Distance = πr/10 ×10

= πr m

as we can see here it covers the half circle ....so the displacement which is the minimum distance between the starting and final point will be The diameter .

Displacement= 2r.

Answer ->>

• Distance = 7πr m
• Displacement = 2r m