What is the magnitude of the net force causing the box to accelerate? What direction will it accelerate?

15 N North

Explanation:

From the question given above, the following data were obtained:

Force of air (Fₐ) = 40 N North

Force of gravity (F₉) = 25 N South

Net force (Fₙ) =?

The net force causing the box to accelerate can be obtained as follow:

Fₙ = Fₐ – F₉

Fₙ = 40 – 25

Fₙ = 15 N North

Thus, the net force causing the box to accelerate is 15 N North

air exerts forces on falling objects near earth’s surface.

explanation:

the term 'free falls' refer to object that are falling towards the earth, in a situation in which gravity is the only force acting on the object.

for an object in free fall, the acceleration is constant (g, the gravitational acceleration), and so the velocity of the object constantly increases.

for objects near earth's surface, there is always another force acting on the object: the resistance due to the air. this force is opposed to the direction of fall of the object, and it is proportional to the velocity of the object, so as the object falls down, this force increases up to a point when it balances the force of gravity, and the object continues its motion at constant velocity (called terminal velocity). since in this case gravity is not the only force acting on the object, we are not in a situation of free fall.