If a water droplet falls from a height in air,its terminal velocity will be attained when the drag force is
Correct answer: D. Equal to the weight of the droplet
- A. Twice the weight of the droplet
- B. Thrice the weight of the droplet
- C. Half of the weight of the droplet
- D. Equal to the weight of the droplet
Explanation
At terminal velocity, a falling object moves at a constant speed because the net force acting on it is zero. This occurs when the drag force, which opposes the motion, equals the gravitational force (weight) acting on the object. Therefore, the correct answer is that the drag force is equal to the weight of the droplet. The other options describe scenarios where the forces are unbalanced, leading to acceleration rather than maintaining a constant velocity.
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About Terminal Velocity
Terminal velocity is the constant speed reached when gravitational force is balanced by fluid resistance. The topic covers drag, buoyant force, the conditions for zero acceleration, and how viscosity, object size, shape and density affect the limiting speed, with a distinction between free fall before and after terminal velocity.
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