Unable to understand relative motion If you sit in a fast moving car on a highway, you will see the objects outside the window moving backwards with respect to you. Assume that your motion is uniform. One would think that all static objects would move backwards with uniform speed.
However, in real, if you sit in the backseat of a van, you will find the background move at a very fast speed from your window. However, if you look through the window of the people sitting in front, the landscape doesn't move as fast. If you carefully follow one part of the landscape (say a stationary patch of grass, or a moving car), you will see it accelerating as it reaches your window.
Why is this so?
P.S. I don't know much physics, so please explain simply.
 A: You are correct that all exterior static object move backwards with uniform speed.  The rest is geometry and psychology, not physics.  The geometry part comes if you watch a near object and far background simultaneously.  If you draw the line from your eye through the near object to the background, it sweeps rapidly backward across the background.  One tends to interpret this as the background moving with you and the near object moving rapidly backward.
A: As you are telling to explain simply,take this example.Take a compass.Put its pointed end on a piece of paper.Take the distance between the fixed arm and the free arm(one to hod the pencil)be 1 cm.Hit it and see it rotate and observe its speed.Now,increase the distance between the two arms to 3 cm.Hit it with a same force.You will see that the speed(more specifically the RPM of the free arm)decreases.Why this is so?Because as the radius increases,the circumference of the circular path also increases.So,the compass has to travel a larger distance.As,time=distance/speed we see that time increases with increases distance.As time increases speed decreases as speed=distance/time.Try to take the idea and implement it in your case.Hope you will be able to get the answer to your question why the distant objects appear to move slower than the nearer objects.
A: I agree with ross answer .If you are asking what Kyle just commented then perspective view apply here.If we consider 5 points or objects outside window  of bus then drawing parallel lines from it to background will give us single point called vanishing point.The objects that passed by the bus in unit time will be equivalent to that vanishing point passing by.It somewhat pschological.
