But what will change?
 Fred |
 Lilly |
„So, now we know, that the water level will rise.“
„Can a higher water level be of importance?“
„Yes, of course. Imagine it in your mind, above every piece of area on the ground of the tub there is a higher water column. Thus a higher pressure on the ground of the tub is generated.“
„And how does a higher pressure influence the speed of the water while draining off?“