4(a) Why doesn't the water flow out when the hand that presses the cardboard is removed? *
1. water inside glass is lighter
2. there is much water inside the glass
3. cardboard is supported by air pressure
4.
cardboard is strong enough to hold the water
Air pressure is the weight of a column of air pushing down on an area. ... Because of the air pressure pushing up on the card, the card will stay on the glass and the water will not spill out.
