Concept:Newton's First Law states that if the net force on an object is zero, its acceleration is zero, resulting in a constant velocity.
Formula:$$ F_{\text{net}} = mg - F_D = 0 \implies a = 0 $$
Solution:- As the droplet accelerates due to gravity, its velocity increases, which in turn increases the opposing drag force.
- Eventually, the drag force \( F_D \) grows large enough to exactly balance the gravitational weight \( mg \).
- At this equilibrium, net force is zero. Acceleration ceases.
- The droplet continues to fall at a steady, maximum constant speed known as "terminal velocity".
Why other options are incorrect:If forces balance, acceleration is zero, eliminating Options C and D. It won't stop (Option A) because the object maintains its inertia (velocity) from the moment the forces balanced.
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