but that is what it's practiced actually like in the hurt of reference this is your normal frame of reference you father thought moving in the circle because you're high moved along with the car you put yourself in the frame of reference of the moving truck so if it isn't always true that we view motion from the third frame of reference when the motion is simpler from the moving frame you automatically put yourself and not moving frame now we're going to do another experiment on a relative motion to show how the compare the block today of an object in one printer records to explore all serbian another frame of reference forgiveness drive a spark a certain stark it moves a straight across the table with a speed which is essentially constant because the forces of friction of the made very small this is just the law of inertia an object moves the constant velocity unless an unbalanced force acts on it how you get the same start backwards uh... dougherty and gives it the same started moves back in this direction with the same philosophy now we're on a car here a car which can move in which were you going to move in this direction and we're going to repeat the experiment all right let's go