Answer:
Parachute exerts a force of 619.2 N upward
The net force is 86.4 N acting downward
Explanation:
As the gravitational acceleration g = 9.8 m/s2, the parachute help reduces the net acceleration to 1.2m/s. So it must exerted an upward acceleration on the skydiver of
9.8 - 1.2 = 8.6 m/s2
Since the skydiver mass is 72 kg, we can use Newton's 2nd law to calculate the force that causes this acceleration of 8.6
F = ma = 8.6*72 = 619.2 N acting upward
The net force is also the product of net acceleration and mass
= 1.2 * 72 = 86.4 N acting downward
The correct answer is:
<span>A. orbiting closer to the earths surface.
In fact, the gravitational force exerted by the Earth on the satellite is
</span>

<span>where
G is the gravitational constant
M is the Earth mass
m is the satellite mass
r is the distance of the satellite from the Earth's surface
We can see that, if the satellite orbits closer to the Earth's surface, its distance r from the centre of the planet decreases. But when r decreases, F (the gravitational force) increases, so A is the correct answer.</span>
When plane is flying along the wind then we can say



Now when its going against the wind the speed is given by



Now by the above two equations we will have


The moment of a couple is Force × perpendicular distance from the arm of the line of action
so the arm of the couple= moment of couple/force=8.5/34=0.25m
the arm is 0.25m