Put the glass down today !
Once a professor began his class by holding up a glass with some water in it. He held it up for all to see and asked the student,"How much do you think this glass weights ?" "50 gms!"... "100 gms!"... "125 gms!"... the student answered. "I really don't know unless I weigh it," said the professor, "but, my question is: What would happen if I held it up like this for a few minutes?" 'Nothing' ..the students said. 'Ok what would happen if I held it up like this for an hour?' the professor asked. 'Your arm would begin to ache' said one of the student. "You're right, now what would happen if I held it for a day?" "Your arm could go numb, you might have severe muscle stress & paralysis & have to go to hospital for sure!"... ventured another student & all the students laughed. "Very good." "But during all this, did the weight of the glass change?"...