Bernoullis Principle What does Bernoullis principle state The

Bernoulli’s Principle

What does Bernoulli’s principle state? The pressure of a fluids flowing horizontally decreases as the speed of the fluid increases. Only applies for steady flow Flow follows streamlines

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Common Applications

Bernoulli & Flight Bernoulli’s Principle is what allows birds and planes to fly. The secret behind flight is ‘under the wings. ’

AIRFOIL On top: greater air speed and less air pressure On bottom: less air speed and more air pressure net force: upward

LIFT THRUST DRAG GRAVITY

Bernoulli & Racecars Spoiler provides better traction and avoids lift

SPOILER – airfoil reversed less air speed more pressure net force: downward greater air speed less pressure

Other Applications

Paper Lift What happens to the paper when you blow across the top? Paper rises Why? Breath speeds air molecules which decrease pressure on top of paper The pressure under the paper pushes the paper up

Inverted Umbrella Use Bernoulli’s principle to explain why your umbrella inverts on a windy day. Wind blows on top of umbrella Air molecules speed up on top f umbrella; therefore, pressure decreases on top of umbrella Air under umbrella which has greater pressure pushes up and inverts umbrella

Shower Curtain Use Bernoulli’s principle to explain why your shower curtain blows inward with a hot shower. Hot inside shower Air molecules speed up inside shower; therefore, pressure decreases inside shower Air outside shower with more pressure pushes shower curtain in