Question

. John completes two rounds around a circular track of length 250 metres. Find the distance covered
by John and also find the displacement.
​

Answer 1

Answer:

Distance in circular motion = Circumference of the circle

As we know, circumference of the circle is denoted by

2 \pi r2πr

Distance=

2 × \frac{22}{7}

7

22

× 20

= 125.7 metre

This means he completed one round in 40 seconds. Thus, he takes 40 seconds to complete one round

Now for 3 minutes= 180 seconds

now taking the ratio,

\frac{125.7}{40} = \frac{x}{180}

40

125.7

=

180

x

Thus,

\frac{125.7*180}{40}=x

40

125.7∗180

=x

Thus

x=565.7

Thus he covered a distance of 565.7 metre in 3 minutes

for displacement let's divide the covered distance by circumference

=565.7/125.7

=4.500

Now converting this in words

this means he has completed 4 rounds and have completed 1/2 round extra, he is on a point parallel to his starting point

thus he is not on his starting position, thus his displacement is not zero. Drawing a line from starting position to his current position, it will pass through the centre, it is the diameter

Displacement= 2×20

= 40m

ANS Distance covered in 3 minutes is 565.7 m and displacement is 40m