Concepts Of Physics MCQ Edition [Volume 1]PhysicsRest and Motion Kinematics
Select the correct statements for a particle travelling on a straight line:
Options
- AIf the velocity remains zero for a time interval, the acceleration is zero at any instant within that time int
- BIf the velocity is zero at a specific instant, the acceleration must also be zero at that instant.
- CIf the velocity and acceleration possess opposite signs, the object is slowing down.
- DIf the position and velocity possess opposite signs, the particle is travelling towards the origin.
Correct answer
D. If the position and velocity possess opposite signs, the particle is travelling towards the origin.
Step-by-step solution
For statement 1: If velocity v = 0 for a time interval, it means velocity is constant during that interval. Therefore, acceleration a = dv dt = 0 at any instant within that interval. This statement is correct. For statement 2: If velocity is zero at a specific instant, acceleration need not be zero. For example, at the highest point of a vertically projected body, v = 0 but a = -g 0 . This statement is incorrect. For statement 3: If velocity and acceleration have opposite signs, the acceleration acts in the directi