Question

A boy completes a semicircle of radius 14 m in 10 seconds. The distance travelled by the boy is

Answer 1

Given:

A boy completes a semicircle of radius 14 m in 10 seconds.

To find:

Distance travelled by the boy ?

Calculation:

Distance is defined as the total path length travelled by the boy. Distance is always positive and is a scalar quantity. Hence it has only magnitude and no directions.

$\therefore \: distance = \dfrac{2\pi r}{2}$

$\implies \: distance = \pi r$

$\implies \: distance = \dfrac{22}{7} \times 14$

$\implies \: distance = 44 \: m$

So, distance travelled by boy is 44 metres.

Addition information:

• In this question if it has been asked to find displacement then the answer would have been :

Displacement = 2r = 2 × 14 = 28 metres.