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Every living thing on Earth is in balance with the pressure of the air or water around it. Pressure helps blood to move around the body and allows organisms to breathe.
What is the meaning of 'pressure'?
Force per total area
Mass per unit area
Force per unit area
What is the unit of pressure?
Kilogram metres per second (kg m/s)
What are fluids?
Liquids and gases
At what angle does a force act on a surface when pressure is being calculated?
Why are liquids used in hydraulic systems instead of gases?
Liquids are difficult to compress and so can transmit forces better than gases
Liquids are easy to compress so forces are transmitted through them well
Liquids have a high boiling point so can transfer pressure better than gases
What is the formula for calculating pressure at the surface of a fluid?
Pressure = force normal to a surface ÷ area of that surface
pressure = force normal to a surface × area of that surface
pressure = mass ÷ area
A force of 10 N acts over a surface area of 2 m2. What is the pressure?
A force of 3 kN acts at right angles to a wall of area 12.5m2. What is the pressure that is exerted on the wall?
Why is a sharp knife better for cutting cheese than a blunt knife?
The sharp knife has a larger cutting area
The sharp knife has a smaller cutting area
The blunt knife has a smaller cutting area
A man wearing skis exerts a pressure of 205 Pa on the snow. The skis have a combined area of 4 m2. What does the man weigh (what is his force)?