When a body falls freely through air, the force acting on it due to gravity is neutralised by the opposite force of air resistance. So, the net force becomes zero. Why then does the falling body not stop falling but still keep falling with a constant velocity( terminal velocity)?
A: This is one of the most common doubts students have while learning about terminal velocity. If the force of gravity pulling down equals the force of air resistance pushing up, shouldn’t the body just stop in the air?
The answer lies in Newton’s laws of motion.
When the two forces balance, the net force becomes zero. With no net force acting, the body can no longer accelerate, but it will continue moving at the same constant speed it already had. This speed is called terminal velocity.
That’s why the body doesn’t stop falling; instead, it keeps descending steadily.
Key Takeaway:
Before forces balance → The object accelerates downward.
When forces balance → No more acceleration, but motion continues.
Result → The object falls at a constant speed = Terminal Velocity.