Question

an athelete completes one round of a circular track of diameter 10m in 20s. calculate the distance and diplacement at the end of 30s.

Answer 1

Hiii...
Here is your answer..

Solution:-
Diameter is given=10m
So,Radius =10/2
$= > 5m$
Since we know that,
Distance travelled=Circumference of the circle=2πr
Therefore,
Distance travelled=
$= > 2 \times \frac{22}{7} \times 5 \\ = > 31.4$
$= > 31(approximately)$
Now,
Since he completes 1 round in 20seconds.
So,
The round completed in 30s=
$= > \frac{30}{20} \\ = > 1.5$
That is,1 and half of the circle.

•Displacement is the shortest distance initial and final velocity.

And after 30 second ,he is opposite side of the starting point.Hence,the Displacement will be:-
$= > 2r \\ = > 2 \times 5 \\ = > 10m$
Therefore,
Distance travelled=31m
Displacement=10m

Hope it helps uh...