Motion in Two or Three Dimensions

It may seem in many cases that an object can be always be considered in only one dimension if the reference frame is changed. A car moving at 5 m/s at an angle of 45 degrees to the horizontal appears as if it is moving in two dimensions, but if the reference is rotated 45 degrees, the car is only in one dimension. This is not always the case especially if more then two objects are involved or if more then two forces are involved. However, this chapter will only discuss the kinematics of motion and not the real cause behind it.