Jump Start #11) A standing wave has areas that don’t leave the

rest position. These are called.A – NodesB – CrestsC – TroughsD – Compression

Jump Start #12) A transverse wave causes the medium to vibrate:

A – Parallel to the direction the wave movesB – At right angles to the direction the wave

travelsC – Only in one directionD - Randomly

Jump Start #13) A longitudinal wave does not have crests and

troughs like a transverse wave. A longitudinal wave has:

A – CompressionB – SurfaceC – RarefactionD – Both A and C

Jump Start #14) A transverse wave is traveling along a slinky on a

table. When that wave reaches the end of the slinky, which is being held still, the wave will:

A – Reflect back in the opposite directionB – Lose energy and disappearC – Change into a longitudinal waveD – Increase in amplitude

Jump Start #15)Label the parts of the wave below using the

following terms:

AmplitudeCrestWavelengthTrough

Jump Start #16) If a wave pulse on a slinky travels 10 meters in 2

seconds what is the speed of that wave? (speed = d/t)

A – 10 m/sB – 5 m/sC – 12 m/sD – 20 m/s

Semester Overview1. Waves2. Electricity and Magnetism3. Motion and Forces4. Energy5. Work and Power

Waves

What comes to mind?

http://www.youtube.com/watch?v=Qf0t4qIVWF4&safety_mode=true&persist_safety_mode=1

Energy and Waves

Mechanical Wave – when a source of energy causes a vibration to travel through a medium.

What is a medium?

Air Vortex Canon

Parts of a Wave

• Medium• Crest• Trough• Compression• Rarefaction• Frequency• Period• Hertz

• Wavelength• Speed• Amplitude• Mechanical Wave• Transverse Wave• Surface Wave

Breaking Sound Barrier

• http://www.youtube.com/watch?v=7HbMcg-quwA

• http://www.grc.nasa.gov/WWW/K-12/airplane/sndwave.html

How Fast Can Waves Travel?

Speed of Sound 343 meters/second1,125 feet/second

768 miles/hour

WOW!!!

How Fast Can Waves Travel?

Speed of Light 299,792,458 meters/second186,000 miles per second 669,600,000 miles/hour

That’s nearly 7 and ½ times around the equator of the earth in 1 second.

Wave Speed

Speed = Wavelength X Frequency

What is Frequency?

The number of complete cycles in a given time.

Frequency is measured in cycles per second or hertz (Hz)

Frequency of Waves

Making Waves

Use the string and a ruler to make waves with the following properties:

1) Wavelength = ½ meter

Making Waves

Use the string and a ruler to make waves with the following properties:

1) Wavelength of 10 centimeters

Making Waves

Use the string and a ruler to make waves with the following properties:

1) Amplitude of 20 centimeters

Making Waves

Use the string and a ruler to make waves with the following properties:

1) Amplitude of 5 centimeters

Making Waves

Use the string and a ruler to make waves with the following properties:

1) Wavelength = 25 centimeters and Amplitude of 10 centimeters