Three forces act on a moving object. One force has a magnitude of 81.2 N and is directed due north. Another has a magnitude of 47.9 N and is directed due west. What must be (a) the magnitude and (b) the direction of the third force, such that the object continues to move with a constant velocity? Express your answer as a positive angle south of east.

Answer 1

X = -47.9 N.
Y = 81.2 N.
Q2.

a. F3 = Sqrt(X^2 + Y^2)

b. Tan A = Y/X = 81.2/-47.9 = -1.69520.
A = -59.5o = 59.5o N. of W.

Direction = 59.5o S. of E.