Question

an athlete completes one round of a circular track of diameter 200m is 30 seconds. find (1)the distance travelled by the athlete and (2)the magnitude of the displacement of the athlete at end of 30 second​

Answer 1

Answer:

• 628.57 metres
• 0 metres

Explanation:

Given:

diameter of the circular track = 200 metres

Radius of the circular track = $\frac{200}{2}$= 100 metres

Time taken = 30 seconds

To find:

• Distance travelled by the athlete
• Displacement at end of 30 seconds

Distance travelled will be equal to the boundary (circumference of the circle)

Circumference of the circle = $2 \pi r$

Circumference of the circle = $2 \times \frac{22}{7} \times100$

Circumference of the circle = $\frac{4400}{7}$

Circumference of the circle = 628.57 metres

The distance travelled at the end of 30 seconds will be equal to 628.57 metres

At the end of 30 seconds the athlete will come back to the initial position which means displacement =0

1. 628.57 metres
2. 0 metres

Answer 2

Answer:

Explanation:

Given :-

Diameter = 200 m

Radius, r = 200/2 = 100 m

Time taken, t = 30 seconds

To Find :-

1. The distance traveled by the athlete.

2. The magnitude of the displacement of the athlete at end of 30 second​.

Formula to be used :-

Distance traveled, means circumference of circle,

i.e, circumference of circle = 2πr

Solution :-

Putting all the values, we get

Distance traveled = 2πr

⇒ Distance traveled = 2 × 22/7 × 100

⇒ Distance traveled = 4400/7

⇒ Distance traveled = 628.57 m

Hence, the distance traveled by athlete is 628.57 m.

Now, magnitude of the displacement,

At the end of 30 seconds, athlete will come to starting position or initial position, so displacement is zero.