Pressure in Fluids Flashcards
All 5 cards in this deck
What is a fluid?
A substance that can flow — a liquid or a gas.
Why does atmospheric pressure decrease with height above the Earth's surface?
There are fewer air molecules above you, so less weight of air pushing down; the air is also less dense higher up.
What causes the total pressure at a point in a liquid such as the sea?
The pressure due to the liquid above that point plus atmospheric pressure pushing down on the surface.
True or false? The atmosphere has the same density at all heights.
False. The atmosphere is densest near the Earth's surface and gets less dense with height.
True or false? At sea level a diver at the water surface experiences zero pressure.
False. Atmospheric pressure still acts on them, about Pa.