Problem dealing with Newtons First Law

[shawonna23]

A 75 kg water skier is being pulled by a horizontal force of 620 N and has an acceleration of 2.1 m/s2. Assuming that the total resistive force exerted on the skier by the water and the wind is constant, what force is needed to pull the skier at a constant velocity?

? N

[maverick280857]

Once again, you should've included your solution.

Anyway, you're given all the three things: F, m and a. So evidently, simply plugging in F = ma is going to land you nowhere. Think of what the problem gives you and what it doesn't. Can you extract the unknown (hint: also constant) quantities from the data and use it for part 2? What does the phrase "constant velocity" translate in terms of forces?

Hope that helps...

Cheers
Vivek