Falling in a Fluid

Velocity & Acceleration

Question 1

a. Starting with eqn. (3.4), determine the velocity of a skydiver (in m/s and mi/hr) falling in air 10 seconds after the fall is initiated.
Assume that k = 0.2 Ns2/m2 and that m = 80 kg.

b. Compare this result with that of a skydiver falling in a vacuum, (Falling in a Vacuum, question 2) and explain the difference.

Question 2

What is the velocity of a skydiver after he or she has fallen 3000m? Assume k = 0.2 Ns2/m2 and m = 80 kg.

Question 3

a. What is the acceleration of the skydiver after he or she has fallen 3000 m?

b. In A Common Skydive, the skydiver free falls 7000 ft. (2134 m). What is the skydiver's acceleration when the ripcord is pulled?

Question 4

Replace vf in eqn (3.2) using eqn (4.1) and obtain the equation for how af varies with y.

Question 5

The functions in eqns (4.1) and Question 4, part a, show how the velocity and acceleration of an object falling in a fluid depends upon y, the distance fallen. Plot vf and af vs. y for 0 ≤ y ≤ 3000 m.

Now proceed to discover.

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