Science teachers are taking classes. Suddenly he saw his student Montu sleeping.
Teacher: Montu ... Uh ... are you sleeping in class? Courage is not less!
Montu jumped up and down: Sir, I haven't slept ...
Teacher in an angry voice: Aren't you sleeping with your head on the bench?
Montu: Sir, what did you say? I was teaching you about gravity ... I was doing a little practical ... You are right sir.
Teacher: You mean ?!
Montu: Sir, as soon as I let go of the weight of the head, it was going down with the neck ... I mean by the pull of gravity ... the head on the bench ...
Teacher: Oh my God ... where did I come from!
ren't you sleeping with your head on the bench? Montu: Sir, what did you say?