Question

a particle is moving with uniform velocity is it necessary moving with uniform speed? is it necessary that it is moving along a straight line ?

Answer 1

Dear student
When we talk about velocity, it certainly means a fixed direction and magnitude may or may not equal throughout the time. But Uniform velocity means both magnitude and direction of velocity will be constant. Thus a body having uniform velocity will also have uniform speed.
If uniform velocity is linear then it must be in straight line because a change in direction will change the velocity.
Regards