Physics Discussion Response

Please read each discussion,in a paragraph or two each tell what you like/dislike, agree or disagree with. Make sure you understand the physics involved. Please keep separate.

Discussion 1:

As the sky diver sits in the plan, no forces are acting or causing him to have motion. His velocity in the plane equals the velocity of the plane. His velocity will increase downward for a moment as he is falling.  However, once the parachuter jumps and the parachute opens, surface are of the diver greatly increases, causing resistance to drastically rise, changing velocity and acceleration in different directions. The change will go from downward to upward. This means that the net force that is acting on the man is upwards causing the downward motion of the man to slow down. The drag, or net force, will constantly act but will begin to decrease until it once again equals the weight of the man. Once the net force upward, or drag from the parachute, equals the body weight of the man, his acceleration will once again increase pulling him downwards. 

Discussion 2:

When jumping off the plane the initial velocity is 0 and the only force acting on the person is. The skydiver’s terminal velocity will be determined by weight and gravity (9.8m/s^2). Air resistance will create drag force (D) which will be proportional to the velocity. When the skydiver opens his parachute it will further increase the drag force since the cross-sectional area is increased which will then lower his terminal velocity. The new slower constant speed will be the new terminal velocity