**A body of mass 2 slugs is dropped with initial velocity zero, but encounters air resistance that is equal to 4 times the square of its velocity. Find an expression for the velocity of the body at time t in seconds.**

**Answer:**

Initial velocity u = 0

Let velocity at any time t is v

Retardation r= 4v^2

Applying Law of Motion

V = u – rt

V = 0 – 4v^2t

4v^2t +v =0 , it is the desired expression of velocity in terms of time t