Bus

[AnthreX]

I was in the bus travelling at 100km/h going to N and i saw another bus going to direction S at the same speed and the same bus

and when the other bus that was heading S passed by ( it was 80~100cm between the buses )
i felt the bus shake and heard a swoosh sound ( the window was open on my seat )

why is that ?

[Integral]

Large vehicles, such as buses, push a lot of air out of the way as they move down the road at high speeds. What you heard and felt was this air pushing on your bus. Perhaps I did not get the full meaning of your question.