Can an object have a constant speed and a varying velocity at the same time?

Question

Can an object have a constant speed and a varying velocity at the same time?

Answer 1

Yes, it can. If it is travelling in circular motion. The speed is constant, yet the direction is constantly changing. As speed is a scalar quantity i.e. it only has magnitude and velocity is a vector quantity, i.e. it has magnitude and direction, a body can change velocity but have constant speed.

As a side note, some say that a body travelling forwards, then backwards at the same speed has constant speed but varying velocity. This I disagree with, as the body would have to pass through a state of having no speed to achieve this, hence both the speed and velocity vary here.

Answer 2

Yes, if it is moving in a circle at a constant angular velocity.

The speed (scalar) is constant, but the velocity (vector) is changing because the angle is changing.

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Answer 3

Yes if it's not travelling in a straight line. Speed is a scalar so just has a magnitude (eg. 10k/h) whereas velocity is a vector and so has a directional component as well as a magnitude (eg. 10k/h in a northeasterly direction).

In fact the only time when the velocity /doesn't/ vary is when an object moves in a straight line at a constant speed.

Answer 4

travelling in a circle.Speed is constant and every moment the direction is changing which is states that velocity is changing