Which of these is an example of dynamic equilibrium?
AA book lying on a table
BA ladder leaning against a wall
CA bridge supporting a static load
DA raindrop falling at terminal velocity
Answer & Solution
Correct answer: D. A raindrop falling at terminal velocity
1. Dynamic equilibrium means net force is zero but the body keeps moving with constant velocity.
2. At terminal velocity, gravity is balanced by air drag, so net force is zero.
3. The raindrop continues to fall at constant speed.
4. The other three are static cases of bodies at rest.
_Source: Selina Concise Physics ICSE Class 10, Ch 1 'Force' (icsehelp.com chapter extract)_
Related questions
Two stones of very different mass are released from the same height with air resistance igAccording to Newton's law of universal gravitation, the force between two point masses depWhich statement is true of the two forces in a Newton's third law action-reaction pair?A fly hits the windscreen of a moving car. Compared with the force the fly exerts on the wA person stands on a bathroom scale inside a lift. The lift begins to accelerate downwardsA lift hangs on a cable and moves upwards at a constant velocity. What is the resultant foIn Newton's second law, how is the acceleration of a body related to its mass?What name is given to the property that makes an object keep doing what it is already doin