Question about terminal velocity

[preluderacer]

Homework Statement

An object of weight W falls from rest subject to a frictional drag force bv^2. What maximum ("terminal") velocity will it approach if W = 4 N and b = 3 N∙ s2/m?

The Attempt at a Solution

I set W = Bv^2 and solved for v and got 1.15. I am not quite sure if this was the method of doing this. Some insight would be nice.

 

[cepheid]

Yeah, at the point where the drag force equals the weight, the net force on the object will be zero, meaning that it will no longer accelerate (by Newton's second law). Hence, it continues to fall at a constant velocity, the terminal velocity.

That's why equating the two forces is the method used to solve the problem.

 

[preluderacer]

Thank you, sometimes I am able to solve problems, but can't explain why!