Question

What is the distance of a car that travels half a lap along a circle of radius of 70 m?

Answer 1

Explanation:

The answer is 300 m. The direction depends on where the car starts. In this case, I assumed the car’s position on the left side of the circle.

Displacement, a vector quantity, is the distance from the initial position to the final position. In this case, the car starts at Point A and stops at Point B. We know that the radius is 150 m, hence the diameter is 300 m. The car stops travelling half way around the circle which is the final position and the initial position is at the other half of the circle, in other words the opposite side. The distance between these positions is the displacement magnitude which is 300 m, the diameter or 2 times the radius.

Answer 2

Answer: 220 m

Given Information: A car travels half a lap along a circle of radius of 70 m.

To Calculate: Distance covered by the car.

Calculation: As per the provided information in the given question, we have :

• Radius of the circle = 70 m

Here, the car travels half a lap along a circle, this means distance covered by him will be the half of the circumference of the circle or we can say that the perimeter of the semi-circle.

$\longmapsto\rm { Distance \; covered = \dfrac{Circumference}{2} }$

$\longmapsto\rm { Distance \; covered = \dfrac{2\pi r}{2} }$

$\longmapsto\rm { Distance \; covered = \dfrac{\Bigg (2 \times \cfrac{22}{7} \times 70\Bigg )\; m}{2} }$

$\longmapsto\rm { Distance \; covered = \dfrac{\Big (2 \times 22 \times 10\Big )\; m}{2} }$

$\longmapsto\rm { Distance \; covered = \dfrac{440 \; m}{2} }$

$\longmapsto\bf { Distance \; covered = 220 \; m }$

Therefore,

• Distance covered by the car is 220 m.