Question

a boy is moving on semi circle of radius 10 cm find the distance and displacement covered by the boy​

Answer 1

Given that,

Radius of semicircle is 10 cm

To find,

The distance and displacement covered by the boy​.

Solution,

Distance = total path covered

Displacement = shortest path covered

The distance covered by a boy is equal to the perimeter of semicircle. So,

$d=\dfrac{2\pi r}{2}=\pi r$

So,

$d=\pi \times 10 = 31.41\ m$

Displacement covered by a boy is equal to the diameter of the semicircle. So,

D = 2r = 2(10) = 20 m

So, the distance and displacement covered by the boy is 31.41 m and 20 m respectively.