Question

a helicopter cruises at a constant velocity when the total thrust of the engines is 5,000 N. How much air resistance acts on the jet ??

Answer 1

Hi there!

`\large\boxed{F_(A) = -5000N}}`

For an object to be moving at constant velocity:

∑F = 0 (The sum of the forces acting on the object MUST be 0 N)

We can do a summation of forces for this helicopter in the HORIZONTAL direction:

∑Fₓ = Ft (Force of Thrust) + Fa (Force of air resistance) = 0

Thus, if we substitute in the given value for Ft:

Ft = -Fa

5000N = -Fa

Fa = -5000N