Question

A magician fills up one-third of a glass with water. He places a card over the mouth of the glass and inverts it. The water doesn't fall. Pick the correct explanation for this phenomenon

• A. air pressure outside the glass is more than the weight of the water in the glass.
• B. air pressure outside the glass is less than the weight of the water in the glass.
• C. air pressure inside the glass is more than the weight of the water in the glass.
• D. air pressure outside the glass is less than the weight of the water in the glass.

Answer 1

The correct option is A air pressure outside the glass is more than the weight of the water in the glass.

The water doesn't fall because the air pressure outside the glass is more than the weight of the water in the glass. The air pressure pushes the card upwards with a greater force, thus preventing the water from falling.