Question

An athlete completes a circular track of radius 70 meters in 20 s. The average velocity of the athlete is: *

Answer 1

Given:-

• Radii of the track = 70 m

∴ Circumference of the track = 2πr

[Let π = 22/7]

Circumference = 2 × 22/7 × 70 m = 2 × 22 × 10 m = 440 m

• Time taken to complete one Revolution = 20 s

To Find:-

Average speed of the athelete.

We know,

Average Speed = (TOTAL DISTANCE)/(TOTAL TIME)

Average speed = (2πr)/t = (440 m)/(20 s) = 22 m/s (Solution)

@Imperius

Answer 2

Answer is Zero.

Explanation: It asked for avg. velocity, not avg. speed. It is a circular track which means displacement is zero. Therefore, Ans is 0