suppose you are going in a jet plane,and one of the windows breaks due to an accident.what problems do you think you will face?

The plane will undergo explosive decompression as the air pressure inside the plane is much higher than the air pressure outside.

Now, before we go any further - explosive decompression does not mean the plane will explode. It means that the plane decompresses faster than your lungs are able to cope so the air 'explodes' out of your lungs. Your lungs would be injured due to the force generated by air leaving very quickly.

The air inside the plane will be sucked out until the air pressure equalizes. Because there will consequently be very little air left in the plane you would of course need an oxygen mask to breathe.