Question

an athlete completes one round of a circular track of diameter 200m in 4 second what will be the distance covered and the displacement at the end of 2 minutes 20 seconds ​

Answer 1

Answer:distance =21991.2

Explanation

First find circumference

pie*d

=22/7*200

=628.32

Total time in sec= 2*60+20

=140

Total distance = 140*628.32/4

=21991.2

Answer 2

Given:

• Diameter of circular track is 200 m.
• Time take by athlete to cover 200 m is 4 seconds.

To Find:

• Distance covered and displacement at the end of 2 minutes 20 seconds.

Solution:

• Diameter of track is 200 m therefore,
• Radius of track = d/2 = 200/2 = 100 m
• Time taken to cover 1 round = 40 seconds and Total time taken 2 minutes 20 seconds
• 1 min = 60 seconds

∴ 2 min 20 sec = 2(60) + 20

→ 140 seconds.

Distance covered by athelete in one round will be equal to the circumference of circle.

Circumference of circle = 2πr

→ Distance covered = 2π(100)

→ Distance covered = 200π

Thus,

Distance covered in 40 sec = 200π

∴ Distance covered in 140 seconds = 140 \times× 5π

→ 700π

→ 700 × 22/7

→ 100 × 22

→ 2200 m

Hence, Distance covered at the end is 2200 m.

• Now we will find the Displacement

It is given that athelete take 40 sec to cover one round and he ram for 220 seconds.

∴ Total rounds = Total distance covered/Distance covered in one round

→ 700π/200π

→ 3.5 rounds.

Therefore, if he started from point A after 140 seconds he will be at point B.

Hence, Displacement = Point A to B

→ 100 + 100

→ 200 m.

Distance covered = 2200 m

Displacement = 200 m