The drawing shows an extreme skier at three locations on a ski run: (A) a straight section, (B) a circular section, and (C) an airborne phase in which the skier is in free-fall. At the right of the drawing are four possible directions for the net force that acts on the skier. What is the direction of the net force at A, B, and C

A) To advance at a constant speed.

In this case the acceleration is zero, therefore there is no net force

That it advances with a decreasing acceleration.

In this case the net force is in the opposite direction to the movement, created by the friction with the air and the nine

B) force towards the center of the circle

C) is a downward force due to the weight of the body

Explanation:

We must analyze this exercise with the help of Newton's second law

         F_net = m a

so we see that the direction of the net force and the acceleration is the same

let's analyze the situations presented

A) a straight section.

We can have three possibilities

* To advance at a constant speed.

In this case the acceleration is zero, therefore there is no net force

* I advance with increasing acceleration

In this case there is a net force in the dissection of the movement, created by the ski poles

* That it advances with a decreasing acceleration.

In this case the net force is in the opposite direction to the movement, created by the friction with the air and the nine

B) In a circular section.

   In this case there must be a force towards the center of the circle

C9 In the air

In this case there is a downward force due to the weight of the body

In general, a force in the opposite direction to the movement created by friction with the air is not taken into account