WhatsApp Image 2025-04-13 at 12.12.43 (2).jpeg

## Bernoulli's Principle **Objectives** * State Bernoulli's principle * Use Bernoulli's principle to explain lift **Materials** * Paper **Procedure** 1. Hold a sheet of paper in front of you so that the top edge is near your mouth. 2. Blow over the top of the paper. What happens? 3. N...

## Bernoulli's Principle **Objectives** * State Bernoulli's principle * Use Bernoulli's principle to explain lift **Materials** * Paper **Procedure** 1. Hold a sheet of paper in front of you so that the top edge is near your mouth. 2. Blow over the top of the paper. What happens? 3. Now hold two sheets of paper, about 2 cm apart. What happens when you blow between them? **Discussion** When you blow over the single sheet of paper, the paper rises. When you blow between the two sheets of paper, the papers move toward each other. These results can be explained by Bernoulli's principle: > When the speed of a fluid increases, the pressure in the fluid decreases. When you blow over the single sheet of paper, the fast-moving air you blow creates a region of low pressure. The higher pressure below the paper then pushes the paper upward. Similarly, when you blow between the two sheets of paper, the fast-moving air between the sheets creates a region of low pressure. The higher pressure on the outer sides of the sheets then pushes the sheets toward each other. Bernoulli's principle can be used to explain lift. Air travels faster over the top of an airplane wing than under the wing. Therefore, the pressure above the wing is less than the pressure below the wing, and there is a net upward force on the wing (lift). **Checkpoint** 1. State Bernoulli's principle. 2. How does Bernoulli's principle explain lift?