A skydiver, who weighs 682 N, is falling at a constant speed with his parachute open. Consider the apparatus that connects the parachute to the skydiver to be part of the parachute. The parachute pulls upward with a force of 669 N.
(a) What is the force of the air resistance acting on the skydiver?
(b) Identify the forces and the interaction partners of each force exerted on the skydiver.
(c) Identify the forces and interaction partners of each force exerted on the parachute
a) If 669 N is the upward pull and 682 is the downward pull, what additional force is needed to make a net force of zero?
The net force must be zero because (they say) the skydiver has constant speed.
b) They have already told you what the forces are; air resistance, gravity an the parachute straps pulling up. The "interacting partners" are the things applying those forces; (1) the atmosphere (2) the earth and (3) the parachute.
c) The parachute is acted upon by the atmosphere, the cords leading to the skydiver and gravity (its own weight). You figure out the reaction partners.
To find the force of air resistance acting on the skydiver, we need to consider that the skydiver is falling at a constant speed. At a constant speed, the net force acting on the skydiver is zero since there is no acceleration. Therefore, the force of air resistance acting on the skydiver must be equal in magnitude and opposite in direction to the force of gravity.
(a) By taking into account the weight of the skydiver, which is 682 N, and the force exerted by the parachute, which is 669 N upward, we can calculate the force of air resistance by subtracting the upward force of the parachute from the weight of the skydiver:
Force of air resistance = Weight of the skydiver - Force exerted by parachute
Force of air resistance = 682 N - 669 N
Force of air resistance = 13 N
Therefore, the force of air resistance acting on the skydiver is 13 N.
(b) The forces exerted on the skydiver and their interaction partners are:
- Force of gravity: This force is exerted by the Earth downward on the skydiver.
- Force of air resistance: This force is exerted by the air upward on the skydiver.
- Force of parachute: This force is exerted by the parachute upward on the skydiver.
The interaction partners of each force are:
- Force of gravity: The Earth is the interaction partner, as the Earth exerts a gravitational force on the skydiver.
- Force of air resistance: The air (or the molecules in the air) is the interaction partner, as the air exerts a resistance force on the skydiver.
- Force of parachute: The parachute is the interaction partner, as it exerts an upward force on the skydiver.
(c) The forces exerted on the parachute and their interaction partners are:
- Force of air resistance: This force is exerted by the air upward on the parachute.
- Force of skydiver: This force is exerted by the skydiver downward on the parachute.
The interaction partners of each force are:
- Force of air resistance: The air (or the molecules in the air) is the interaction partner, as the air exerts a resistance force on the parachute.
- Force of skydiver: The parachute is the interaction partner, as the skydiver exerts a downward force on the parachute.