Kinematics Reasonings

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

Acceleration is the rate of change of velocity given by \[a=\frac{v-u}{t}\]

Hence, acceleration is zero only when both the velocities $u$ and $v$ are zero. In the question, it is given that the velocity of the object is changing so the acceleration cannot be zero even if one of them becomes zero at that instant.

[Read: Motion in a Straight Line]

For example, when an object is thrown vertically upward, at the maximum height, its velocity becomes zero. But the object has acceleration due to gravity in downward direction.

[Read: Motion Under Gravity]


A player hits a baseball at some angle. The ball goes high up in space. The player runs and catches the ball before it hits the ground. Which of the two (the player or the ball) has greater displacement?

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?

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

A body travels one half of a distance with uniform velocity $v_1$ and the other half with uniform velocity $v_2$. Find the magnitude of the average velocity.

If a body is thrown vertically upward from a vehicle moving with uniform velocity, where will the body fall?