Foods cook faster when placed in a pressure cooker. this is because the pressure on the surface of the water is the atmospheric pressure, and the boiling point of water is normal.

Foods cook faster when placed in a pressure cooker.

This is because in the pressure cooker, the pressure on the surface
of the water is greater than the normal atmospheric pressure.  Under
those conditions, the boiling temperature of water is increased. 

So the food can be heated to a greater temperature than the normal
boiling point of water.  That means that the food gets hotter, and it
cooks through and through faster.