Pressure Notes

Pressure in Solids

• Definition: Pressure is the force acting per unit area.
• SI Units of pressure is pascals.
• Pressure in solids depends on force and area.
• Small surface area = high pressure; large surface area = low pressure.

Real Life Applications of Solid Pressure

• Knife Blade: Small area increases pressure to cut.
• Drawing Pins / Nails: Sharp tip (small area = high pressure); Wide head (large area = low pressure on fingers).
• High Heels vs Flat Shoes: High heels exert more pressure due to small surface area. Flat shoes spread force, reducing pressure.
• Snowshoes: Large area reduces pressure on snow, preventing sinking.
• Hydraulic Press: Pressure applied on a small piston is transmitted to a larger piston.

Pressure in Liquids

• Pressure in liquids increases with depth.
• Pressure in liquids increases with density.
• Pressure in liquids acts equally in all directions.