When a parachute opens, the air exerts a large drag force on it. This upward force is initially greater than the weight of the sky diver and thus slows him down. Suppose the weight of the sky diver is 905 N and the drag force has a magnitude of 1005 N. The mass of the sky diver is 92.3 kg. Take upward to be the positive direction. What is his acceleration, including sign?
ma=-mg +F
a= F/m- g = 1005/92.3 - 9.8 =
=10.9 -9.8 = 1.1 m/s²
To find the acceleration of the skydiver, we need to consider the forces acting on him. The weight of the skydiver acts downwards and has a magnitude of 905 N, while the drag force acts upwards and has a magnitude of 1005 N.
First, let's determine the net force acting on the skydiver. Since the drag force is initially greater than the weight, the net force will be the difference between the two:
Net force = Drag force - Weight
Net force = 1005 N - 905 N
Net force = 100 N upwards
Since the net force is acting in the positive direction (upwards), the acceleration of the skydiver will also be in the positive direction.
Now, we can use Newton's second law of motion to find the acceleration:
Net force = mass × acceleration
Solving for acceleration:
acceleration = Net force / mass
acceleration = 100 N / 92.3 kg
acceleration ≈ 1.08 m/s²
Therefore, the acceleration of the skydiver, including the sign, is approximately 1.08 m/s² upwards.