The plot shows the velocity of a parachuter for three cases: (1) free fall, (2) when the parachute opens suddenly after 30 seconds of free fall, and (3) when the parachute takes three seconds to open. In the first case, the parachuter reaches terminal velocity. In the second case, the shoulders of the parachuter are sharply strained since air resistance is proportional to the square of velocity. In the last case, this strain is reduced considerably. The acceleration is plotted after 30 seconds.