Question

1. Is it possible for a car to circle a racetrack with constant velocity? Can it do so with speed? Explain.

(I understand that it's not possible for a car to circle a racetrack with constant velocity. I'm having trouble explaining the second part of the problem.)

Thank you!

Answer 1

To answer this we have to first consider the difference between velocity and speed. Now, velocity is a vector quantity. So it has both direction and magnitude and if any one among these changes , it will change the velocity. That means if the magnitude is constant but direction changes, the velocity changes. On the other hand speed is a scalar quantity. It has only magnitude. Now, in circular track the magnitude of speed can be constant. That means, one can move along the track with constant speed. But every time in this track the direction of movement changes which results the change in velocity. So, to sum up I can say that it is not possible for a body or a car to circle a race track with constant velocity but it can circle with constant speed.