A ball bearing is gently released from rest and allowed to fall through a viscous fluid. Which of the following statements about the motion is correct?
-
its acceleration decreases before terminal velocity is attained
- when terminal velocity is attained the acceleration of the fluid becomes zero
- its velocity increases before terminal velocity is attained
- there is no resultant force on the ball before it attains terminal velocity
The correct answer is: A
Explanation
Its acceleration decreases before terminal velocity is attained:
When the ball bearing is released, it accelerates due to gravity. As it falls, the viscous drag force exerted by the fluid increases. This drag force opposes the weight of the ball bearing, resulting in a decrease in acceleration until terminal velocity is reached.