Bernoulli’s Principle

Natalie O’Neal Vickie Rincones Emily Perkins Brittany Schultz Tenneille Duke

Introduction

• Subject: Science • Objective: To discover Bernoulli’s Principle • Materials: Hair dryer, ping pong balls, balloons, straws, and coke cans • Methods: Notes and experiments • Grade: 8 th grade • Age: 13 & 14 year olds • Languages: 2 - English and Spanish

Strategies

• Sheltered Instruction • Scaffolding by repetition of vocabulary • Cooperative learning by working in groups • Students learn through:  Kinesthetics by performing experiments  Auditory learning by listening to lecture  Visual learning by seeing realia and watching video

Bernoulli’s Principle

• What are we learning today? –

Bernoulli’s Principle

• Why are we learning about it?

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To understand pressure systems and apply them to real life examples

• How are we going to learn?

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We will learn through note-taking and hands on experiments.

• What should we know before we begin?

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Key Terms: Speed, Velocity

Who is Bernoulli?

• 18 th century Swiss scientist • Studied fluid flow in pipes *Fluid = any liquid

Vocabulary

• Speed = Rapidez - how fast something moves Formula: Distance / Time • Velocity = Velocidad direction of motion – speed of an object

and

its • Air Pressure exerted = Presi ó n de Atmosf é rica – the force by air on any surface in contact with it • Lift = Ascender higher position – raise from a lower position to a *Exerted = pushed

Bernoulli’s Principle

• Textbook Definition : When the speed of a fluid increases , internal pressure in the fluid decreases .

• Our Definition : When speed increases, pressure decreases.

*Increase = to go higher *Pressure = a type of force *Decrease = to go lower

High Pressure/Low Pressure

• High Pressure always travels to Low Pressure areas.

Experiments

• Video Link: http://www.youtube.com/watch?v=ctJyu5ete6Y • Hair dryer demonstration • Coke can demonstration

Additional Examples

• 1. Umbrella – The curved part of an umbrella causes air moving across it to have a higher velocity (similar to an airplane’s wing). – On a windy day, the higher velocity creates much lower pressure on the top of the umbrella. – The high pressure under the umbrella pushes up to the lower pressure, causing the umbrella to turn inside out.

Additional Examples

• 2. Faucet and ball – The moving water creates low pressure because of the increased velocity. – The high pressure around the stream pushes the ball towards the low pressure, causing it to touch the water stream.

Additional Examples

• 3. Perfume Sprayer – When you squeeze the bulb, air rushes across the open end of the tube to create low pressure. – Higher pressure on the liquid pushes it up and it is carried away by the stream of air.

Additional Examples

• 4. Insects – Insects increase their lift by flapping their wings forward and backward, not up and down. – The tilt of their wings provide an angle to create low pressure and lift.

Additional Examples

• 5. Shower curtain – When taking a shower, the moving water creates low pressure inside the shower. – High pressure outside the shower moves towards the low pressure, causing the shower curtain to swing against your legs.