when i am walking in our railway station at night i observed a train coming with lights i thought that two trains are coming aside to each other.But it was only one train having two lights .Which property of light makes it look like so, what is the reason of that one
closed as not a real question by David Zaslavsky♦ Jun 7 '11 at 16:59
It's difficult to tell what is being asked here. This question is ambiguous, vague, incomplete, overly broad, or rhetorical and cannot be reasonably answered in its current form. For help clarifying this question so that it can be reopened, see the FAQ.