Transcript Bernoulli`s Principle
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.