Why isn't this working!! 2D Kinematics Here is the problem: Relative to the ground, a car has a velocity of 18.2 m/s, directed due north. Relative to this car, a truck has a velocity of 22.9 m/s directed 47.2 ° south of east. Find the (a) magnitude and (b) direction of the truck's velocity relative to the ground. Give the directional angle relative to due east. For a) I found the answer as follows (which is correct) V of T in relation to G (Vtg) = V of T in relation to C (Vtc) + V of C in relation to G Vcg. The x factor looks like this: Vtgx = Vtc + Vcg 22.9 cos 47.2 + 0 = 15.6 Y factor: Vtgy = Vtc + Vcg -22.9 sin 47.2 = 1.39 Vtg = Sqrt (Vtgx^2 + Vtgy^2) = 15.7 <-------the Right answer For b) I did tan^-1 y/x, but I keep getting the wrong answer. What is going on. I keep getting 5.07, and this is incorrect!