Question

An athlete completes one round of a circular track of radius R in 20 seconds.what will be his displacement at the end of 2 minute 20 seconds?

Answer 1

Solution:-
Time =2minutes 20 seconds
$= > 2 \times 60 + 20 \\ = > 120 + 20 \\ = > 140seconds$
Since,he completes one round in 20 seconds.
So,
In 140 seconds he will cover=
$= > \frac{140}{20} \\ = > 7rounds$

Here,In 140 seconds he completed complete sever round.

Displacement is equal to shortest distance between initial and final position.

Since,when he completed seven round.The initial and final position was same.

Hence,
The displacement will be ,"0"