question_answer 19)

Explain why on looking through the window of a fast moving train, the nearby trees and electric poles etc. appear to run in direction opposite to that of motion of the train, while far off houses, hilltops, Moon, stars etc. appear stationary. 

Answer:

The line joining the object and the eye is called the line of slight. The direction of the line of sight of the nearby objects like trees, poles etc.; changes very rapidly due to fast motion of the train and accordingly they appear to be moving opposite to the direction of motion of the train. But the line of sight of a distant object almost does not change its direction due to its extremely large distance from the eye. Hence the distant objects like hilltops, moon, stars etc. appear stationary.