Question

A car moves in a semi circular track of radius 700 m. If it starts from one end of the track and stops at the other end, then the displacement of the car is
a)2200m
b)700m
c)1400m
d)1500m​

Answer 1

Given,

A car moves in a semi circular track of radius 700 m.

To find,

The displacement of the car.

Solution,

The car is moving along a semi-circular track and the radius of the track is 700 m. [The diagrammatical representation is provided in the picture attached.]

As displacement is the shortest distance between the starting and the ending point, the displacement can be taken as the diameter of the semi-circle.

Diameter = 2r where r = radius.

Substituting the values,

Diameter = 2 x 700 = 1400 m.

Therefore, the appropriate answer to the question is Option C, 1400 m.

Answer 2

Given :-

Radius of the semi circular track = 700 m

To Find :-

The displacement of the car.

Solution :-

We know that,

• s = Displacement
• r = Radius

Displacement is the distance between the final and initial positions.

It is considered as the diameter of the semi circle since the shortest distance between the starting and the ending point.

According to the question,

$\underline{\boxed{\sf Displacement=2 \times Radius}}$

Given that,

Radius (r) = 700

it covers a distance of semi circle and it reaches to the point opposite to the initial point.

Substituting their values,

s = 2 × 700

s = 1400 m

Therefore, the displacement of the car is 1400 m.