1. Pressure Depends on Force and Area

Pressure is calculated by dividing the force applied perpendicular to a surface by the area over which the force acts. The same force produces greater pressure when applied over a smaller area.

2. A Sharp Knife Cuts More Easily

A sharp knife has a very thin cutting edge. Because the force is concentrated over a smaller area, it produces greater pressure, making cutting easier.

3. The Air Around Us Exerts Pressure

Earth's atmosphere exerts pressure on everything around us. At sea level, standard atmospheric pressure is approximately 101,325 pascals (Pa).

4. Pressure Decreases as Altitude Increases

Atmospheric pressure generally decreases with increasing altitude because there is less air above a location. This is why mountain climbers may experience breathing difficulties at high elevations.

5. Water Pressure Increases with Depth

The deeper you travel underwater, the greater the surrounding water pressure becomes. This happens because deeper locations support the weight of more water above them.

6. Pressure Explains Why Snowshoes Work

Snowshoes spread a person's weight over a larger surface area. This reduces the pressure on the snow and helps prevent the wearer from sinking deeply.

7. A Hydraulic Machine Can Multiply Force

Hydraulic systems use pressure transmitted through a confined fluid to transfer force. In a hydraulic press or lift, a small force applied to a small piston can produce a much larger force at a larger piston.

8. Pressure Helps Vehicles Grip the Road

Tire pressure affects the shape and performance of a tire, its contact with the road, handling, and fuel efficiency. Maintaining the recommended tire pressure helps vehicles operate safely and efficiently.

9. Your Ears Feel Pressure Changes During Flights

During takeoff and landing, cabin pressure changes can create a pressure difference across the eardrum. Swallowing, yawning, or chewing can help equalize pressure through the Eustachian tubes.

10. Pressure Cookers Cook Food Faster

A pressure cooker raises the pressure inside its sealed cooking chamber. This increases the boiling point of water, allowing food to cook at a higher temperature and usually reducing cooking time.

11. Pressure Is Essential for Weather Forecasting

Changes in atmospheric pressure help meteorologists understand weather systems. Falling pressure can indicate an approaching low-pressure system, while rising pressure often accompanies more stable weather.

12. Pressure Can Be Measured in Different Units

The pascal is the SI unit of pressure. Other commonly used units include the bar, atmosphere (atm), millimeter of mercury (mmHg), torr, and pounds per square inch (psi).

13. A Straw Works Because of Pressure Differences

When you suck through a straw, you lower the pressure inside your mouth and the straw. Atmospheric pressure acting on the drink's surface pushes the liquid upward through the straw.

14. Pressure Exists Even in Tiny Particles

Gas pressure results from particles moving randomly and colliding with the walls of their container. Increasing the temperature of a gas at constant volume generally increases its pressure.

15. Pressure Can Be Extremely High Deep in the Ocean

In seawater, pressure increases by approximately one atmosphere for every 10 metres of depth. At around 1,000 metres deep, the total pressure is roughly 100 times standard atmospheric pressure, illustrating the extreme conditions experienced by deep-sea organisms and equipment.