Question

an athlete completes one round of a circular track of diameter 200 m in 30 s find distance and displacement.

Answer 1

ANSWER

Distance =$628.57cm^2$.

Displacement =0 m

Step By Step Explanation

We are given that >

The diameter of the circular track= 200m

Time taken to complete one round = 30 s

Now, we know >

Radius = $\dfrac{Diameter}{2}$

=>Radius = $\dfrac{200}{2}$

=>Radius = 100m

Hence, the radius of the circular track is 100m.

Now,

The circumference of a circle = 2πr

$\implies Circumference \: of \: circle = 2\times\dfrac{22}{7}\times100$

$\implies Circumference \: of \: circle = \dfrac{4400}{7}\times100$

=>Circumference=$628.57cm^2$

Hence the distance covered by the athlete is $628.57cm^2$.

But the displacement is 0 here as the athlete starts from the origin point and returns to the same point which means there is no displacement.

Remember

1)Displacement is the distance which is calculated from the origin point and is a vector quantity.

2)It calculates both the direction and distance of motion along a straight line from the initial point of origin to the final point.

3)Distance is a scalar quantity which helps to show how far is a body from another body.

Answer 2

Holaaa Mate

Answer:

Displacement is the shortest distance possible between initial and final position.

As the athlete is in circular motion , displacement is zero. [ THis is because , the initial and final position is the same ]

Distance covered in 1 round = Circumference of the circle

Circumference of the circle = 2πr

Diameter = 200 m

Radius = 100 m

Distance covered in 1 round[ 40 sec ] = 2 × 22/7 × 100 = 628.57 m

Distance covered in 1 sec = 628.57 ÷ 40 = 15.71 m

2min 20 sec = 140 sec

Distance covered in 140 sec = 15.71 × 140 = 2199.4 m