Water in the Cup

Water in the Cup
Science brain teasers require understanding of the physical or biological world and the laws that govern it.

A man in a restaurant asked a waiter for a juice glass, a dinner plate, water, a match, and a lemon wedge. The man poured enough water onto the plate to cover it.

"If you can get the water on the plate into this glass without touching or moving this plate, I will give you $100," the man said. "You can use the match and lemon to do this."

A few minutes later, the waiter walked away with $100 in his pocket. How did the waiter get the water into the glass?

(Scoll Down for Hint)

\/

\/

\/

\/

\/

\/

\/

Hint

The glass will be upside-down when the water is in it.


(Scoll Down for Solution)


\/

\/

\/

\/

\/

\/

\/

\/

Solution

First, the waiter stuck the match into the lemon wedge, so that it would stand straight. Then he lit the match, and put it in the middle of the plate with the lemon. Then, he placed the glass upside-down over the match. As the flame used up the oxygen in the glass, it created a small vacuum, which sucked in the water through the space between the glass and the plate. Thus, the waiter got the water into the glass without touching or moving the plate.

You can try this experiment at home with appropriate supervision.