A boat of mass M sails with velocity v_(0)hati. At t = 0, its engine stops, and at the same time a ball of mass m(m lt lt M) is thrown form the boat with initial velcoity uhatj. Here x-direction is horizontal any y is vertically up. The water exters a friction drag forve proportional to the boat's velocity (v), so that vecF = kvecvhati, where K is positive constant. The acceleration of the boat can be written as: veca =- (kv)/(M)hati or (dvecv)/(dt) =- (kv)/(M)hati intergrating we get: vecv = (Ce^(-Kt//M))hati where C is a constant emerging due to intergraitng. Now assume that ball is observed form the reference frame of boat (X'Y'). The origin of this reference frame coincided with the static frame (XY) at t = 0. The acceleration of the ball in the reference frame of boat can be written as veca = a_(x)hati +a_(y) hatj and in the static frame it can be written as veca = a_(x) hati +a_(y) hatj. The value of constant C is :