We are required to apply our knowledge of forces, velocity, and acceleration.

Newton's second law:

$\overline{){\mathbf{\Sigma}}{\mathbf{F}}{\mathbf{=}}{\mathbf{m}}{\mathbf{a}}}$

Acceleration:

$\overline{){\mathbf{a}}{\mathbf{=}}\frac{\mathbf{\u2206}\mathbf{V}}{\mathbf{\u2206}\mathbf{t}}}$

A ball dropped off of a tall tower will reach its terminal speed (vterm):

Answer

a. if it falls long enough for its speed to increase sufficiently such that the drag force (D) from air resistance becomes equal to the weight of the ball.

b. never - it is impossible for a falling ball to ever reach terminal velocity.

c. as soon as it released and starts to fall.

d. after the ball has fallen a short distance, and the drag force (D) from air resistance starts to act on the ball.

Frequently Asked Questions

What scientific concept do you need to know in order to solve this problem?

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