the magnitude of the skydivers acceleration is zero as he is decelerating by opening his parachute!
80 m/s2 up
If the 0.75 refers to seconds, then his acceleration is -66.66... (repeating) metres per second^2.
80 m/s 2 up
He will decelerate (meaning an acceleration in the direction opposite of current velocity) at a rate of (54 m/s - 4 m/s)/.75 seconds = 66.67 m/s2. This is about 6.8 Gs.
(4 m/s - 54 m/s)/0.75 s = -50/0.75 m/s² = -200/3 ≈ - 66.67 m/s² (negative because he is decelerating)
66.7 m/s2
66.7 m/s2
80 m/s2 up
Sky divers do not go up, but they do undergo deceleration due to the increased drag incurred by the parachute being suddenly opened. Since skydivers, when being filmed by a cameraman, release their parachute first, there is a relative acceleration between the cameraman and the skydiver, creating the illusion that the skydiver is travelling up.
zero
66.7 m/s2
When a skydiver opens the parachute, he or she does not move upward, but rather, continues to move downward, but at a slower speed. Sometimes there is an illusion that the skydiver is moving upward, because if there are several people skydiving together, and one of them opens a parachute while the others don't, you will see the skydiver with the open parachute moving upward with relation to the other skydivers. But they are all still moving downward, they are just doing so at different speeds.
If the 0.75 refers to seconds, then his acceleration is -66.66... (repeating) metres per second^2.
80 m/s 2 up
He will decelerate (meaning an acceleration in the direction opposite of current velocity) at a rate of (54 m/s - 4 m/s)/.75 seconds = 66.67 m/s2. This is about 6.8 Gs.
Acceleration due to gravity is 9.8m/s/s, which is the same as 9.8m/s2. An acceleration of 9.8m/s/s means that with each passing second, the velocity of the skydiver increases by 9.8m/s. Therefore, after two seconds. a skydiver's velocity would be 19.6m/s. The acceleration will continue at 9.8m/s/s until the skydiver reaches terminal velocity, at which point the weight of the skydiver and the air resistance will be balanced, so the net force acting on the skydiver will be zero, at which point there will be no further acceleration.
(4 m/s - 54 m/s)/0.75 s = -50/0.75 m/s² = -200/3 ≈ - 66.67 m/s² (negative because he is decelerating)