Kinematics Reasonings

If a particle is accelerating, it is either speeding up or speeding down. Do you agree with this statement?

No. An accelerating particle does not necessarily speed up or speed down. Acceleration is the rate of change of velocity. The change of velocity means that there is either change of speed or change of direction or both. Even if the speed is constant, the change of direction can give acceleration.

[Read: Motion in a Straight Line]

For example, a particle moving with constant speed $v$ in a circular path of radius $r$ has a centripetal acceleration $a_c$ towards the centre given by \[a_c=\frac{v^2}{r}\]

[Read: Circular Motion]


Is it possible that the displacement of a body is zero but not the distance?

If the acceleration of a body remains constant, is it necessary that the path is rectilinear?

If the velocity of an object is changing and becomes zero at an instant of time, is the acceleration zero at that instant?

Can a body move on a curved path without having acceleration?

Can a body be at rest and motion at the same time?

Is it possible that acceleration of a body is in one direction with motion in two directions?