Question

A sack of potatoes that weighs 200 N falls from an airplane. as the velocity of fall increases, the air resistance also increases. When air resistance equals 200 N, the acceleration of the sack will be

Answer 1

The acceleration of the sack will be zero when air resistance equals 200 N, which is equal to its weight, because the forces are balanced.

Step-by-step explanation:

When the air resistance equals the weight of the falling sack of potatoes, which is 200 N, then the net force acting on the sack is zero. With a net force of zero, according to Newton's second law, the acceleration of the sack will also be zero. This is because the downward force of gravity is perfectly balanced by the upward force of air resistance, resulting in no change in velocity; the sack continues to fall at a constant speed, which is known as the terminal velocity.

Answer 2

When air resistance is equal to the sack's weight, it will no longer accelerate (so its acceleration will be zero) and will be falling at terminal velocity.