Try it on paper first. A hint, the key idea and the worked solution are here when you need them.
A skydiver with an open parachute falls at a steady . Is the skydiver in free fall? How big is the air's upward force on the skydiver and parachute? ()
Free fall: only gravity acts, for every object. From rest, , , . Thrown up at : it reaches the top after at a height .
Have you tried it?
Work it out on paper first. It is fine to get stuck or make a mistake: that is how we learn. When you are ready, go through the solution one step at a time, and check each step against your own.
Step 1. Free fall? No. In free fall only gravity acts and the speed grows by each second. Here the speed stays at .
Step 2. Forces. Steady speed, so the air's upward force balances the weight: .
Answer: Not free fall; the air pushes up with .
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