Answer:
The air resistance on the skydiver is 68.6 N
Explanation:
When the skydiver is falling down, there are two forces acting on him:
- The force of gravity, of magnitude [tex]mg[/tex], in the downward direction (where m is the mass of the skydiver and g is the acceleration due to gravity)
- The air resistance, [tex]R[/tex], in the upward direction
So the net force on the skydiver is:
[tex]F=mg-R[/tex]
where
m = 7.0 kg is the mass
[tex]g=9.8 m/s^2[/tex]
According to Newton's second law of motion, the net force on a body is equal to the product between its mass and its acceleration (a):
[tex]F=ma[/tex]
In this problem, however, the skydiver is moving with constant velocity, so his acceleration is zero:
[tex]a=0[/tex]
Therefore the net force is zero:
[tex]F=0[/tex]
And so, we have:
[tex]mg-R=0[/tex]
And so we can find the magnitude of the air resistance, which is equal to the force of gravity:
[tex]R=mg=(7.0)(9.8)=68.6 N[/tex]
