Bernoulli’s Principle

Some independent research from one of our RGS Physics pupils:

Bernoulli’s Principle was formulated by the Swiss physicist Daniel Bernoulli and it describes how fluids behave. It states that within a stream of fluid, pressure decreases as the speed of flow increases, and similarly pressure increases as speed of flow decreases.

Aircraft wings

The most conman application of Bernoulli’s Principle is in the design of a plane wing. They are curved on top and completely flat underneath. Whilst in flight, the air travels across the top and the bottom concurrently, but, due to the design,  the air on the bottom moves slower, which creates more pressure. Equally, the air on top moves faster which creates less pressure. This effect creates lift and allows the aircraft to fly.

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Bunsen burner

Another application is the Bunsen Burner. When the burner is connected to the gas supply, the gas flows at a high velocity through a narrow tube, creating a region of low pressure. The outside air, which is at atmospheric pressure, is drawn in and mixes with the gas. The mixture of gas and air enables the gas to burn and produce a flame.

Insecticide sprayers


A third application is the insecticide sprayer. When the plunger is pushed in, the air flows at a high velocity through the tube. The flow of air at a high speed creates a region of low pressure just above the tube, which allows the insecticide to leave the tip of the tube through the nozzle as a fine spray, carried by fast moving air.



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