Question

Which of the following situation is possible?
(a)  An object can have acceleration, but constant velocity.
(b) The velocity of an object may be zero but acceleration is not zero.
(c) Distance and the magnitude of displacement are equal in circular motion.
(d) Average speed and the magnitude of average velocity are always equal in circular motion​

Answer 1

Answer:

Which of the following situation is possible?

(a)  An object can have acceleration, but constant velocity.

Answer :: This situation is not satisfied.

• The velocity of an object may be zero but acceleration is not zero.

• Distance and the magnitude of displacement are equal in circular motion.

• Average speed and the magnitude of average velocity are always equal in circular motion.

(b) The velocity of an object may be zero but acceleration is not zero.

Answer :: This situation is satisfied.

• A body may have zero velocity but non-zero acceleration.

• For example, when a body is thrown vertically upwards at the maximum height the body momentarily comes to rest.

• At this point the body attains zero ation due to gravity directed downward.

(c) Distance and the magnitude of displacement are equal in circular motion.

Answer :: This situation is not satisfied.

• Because displacement is the shortest path between initial and find path.

• So, for car moving on straight road, distance moved and magnitude of displacement are equal.

(d) Average speed and the magnitude of average velocity are always equal in circular motion.

Answer :: This situation is not satisfied.

• If the motion of an object is along a straight line and in the same direction, the magnitude of displacement is equal to the total path length$.$

• In that case, the magnitude of the average velocity is equal to the average speed.

Answer 2

This is possible : (b) The velocity of an object may be zero but acceleration is not zero.

But how ?

• Let's assume that we throw a ball with initial velocity of u m/s upwards and it reaches a height 'h' above the earth' surface.

• At the highest point, the velocity of the ball is zero but it is still experiencing the gravitational acceleration of 9.8 m/s² towards the earth' surface.

• So, the velocity is zero but acceleration is not zero.

• So, option b) is correct ✔️

__________________________

Other options are incorrect because :

• With acceleration, an object can never have constant velocity.

• Similarly, in circular motion : distance is not equal to displacement.

• Hence, the speed is also not equal to velocity in circular motion.

$\star$ Hope It Helps