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22. mainidea the skydiver shown in figure 13 falls at a constant speed in the spread-
eagle position. immediately after opening the parachute, is the skydiver accelerating? if
so, in which direction? explain your answer using newton's laws.

Yes, upward

Explanation:

We can solve the problem by using Newton's second law, which can be written as

where is the net force, m is the mass, a is the acceleration.

At the beginning, the skydiver is falling at constant speed (called terminal velocity): this means that the two forces acting on him/her, the weight W (downward) and the air resistance R (upward) are equal in magnitude, and so the net force (and the net acceleration) is zero:

When the parachute is opened, the resistance  force suddenly increased (because the surface area of the body increases), so Newton's second law becomes:

this time, , therefore , which means that the acceleration has the same direction as the air resistance (upward). As a result, the skydiver will accelerated upward, which means that its vertical velocity will decrease in magnitude (because he/she was travelling downward, so the acceleration is in the opposite direction).

i think it’s a. this is because if they measured the mass of something with a mass of 150g, then their final answer would have to be approximately 150g. though all of their answers are almost 150, rosa and tran have the closest answers (or the exact answer) to the accurate one.