Q14DQ

Question

Under constant acceleration the average velocity of a particle is half the sum of its initial and final velocities. Is this still true if the acceleration is not constant? Explain.

Step-by-Step Solution

Verified
Answer

No, the acceleration is not constant.

1Given information

It is given that under constant acceleration, the average velocity of a particle is half the sum of its initial and final velocities.

2Determine whether the given statement is true for acceleration or not

Consider a counterexample.

 

Start from rest (initial velocity 0). Run a kilometer away along a straight line, and then stop, where the final velocity becomes 0.

 

The average velocity is not zero, but the average of the initial and final velocities is 0.

 

As, acceleration is the ratio of change in average velocity to time, so the acceleration is not constant.