Chapter 5, Section 2

Making Waves

February 17, 2012HW: PTG #1, 2, 5-8, pg. 505-506, Due Next Wednesday/Thursday

• Learning Objective:– Describe how waves carry

energy– Describe how wavelength,

frequency and speed of a wave are related

• Success Criteria:– Observe the motion of a pulse– Calculate the speed of a wave

pulse– Observe standing waves– Investigate the relationship

among wave speed, wavelength, and frequency

– Make a model of wave motion– Distinguish between transverse

and longitudinal waves

• Do Now:–Write LO and SC on a new left-side page–WDYS/WDYT pg. 492

Investigate: Part A• Stadium Wave• Standing Wave • #1-Answer a-d in your notebook

Do Now• Draw a wave

• Label as many parts as you can of the wave.

• Read page 494 #4, 5, 6, 7

Part A Big Idea?• Wave moves, but people move up

and down• Waves are produced by adjacent

particles move up and down, causing the wave to move across.

Investigate: Part B• Transverse Waves• Demo #1-2 (answer questions) demo 3-

4 answer question• You are writing in your notebook• #6-7-in groups• #7-choose amplitude as a class– Prediction: How do you think amplitude

will affect the speed of the wave?– Groups 1-2, 3-4, 5-6 different amplitudes

Exit ticket• ON a half sheet of paper…

• Describe how waves carry energy using the following sentence structure about how waves carry energy.– As particles move___________, the wave

moves___________.

February 23, 2012• Learning Objective:

– Describe how waves carry energy

– Describe how wavelength, frequency and speed of a wave are related

• Success Criteria:– Observe the motion of a pulse– Calculate the speed of a wave

pulse– Observe standing waves– Investigate the relationship

among wave speed, wavelength, and frequency

– Make a model of wave motion– Distinguish between transverse

and longitudinal waves

• Do Now:–Read

procedures #10-15–Pg. 496-497–Create data

table

• #10-13 Demo then in groups• #14-Demo, discuss energy• #15-groups, discuss

a. A transverse pulse is one in which the motion of the wave is perpendicular (90 degrees) to the motion of the particles of the medium

b. As the amplitude of a transverse pulse on a spring increases, its speed remains the same

c. As the frequency of a standing wave increases, the wavelength decreases and the wave velocity remains the same.

February 22, 2012HW: PTG #1, 2, 5-8, pg. 505-506, Due Wed, Bring Tissues

• Learning Objective:– Describe how waves carry

energy– Describe how wavelength,

frequency and speed of a wave are related

• Success Criteria:– Observe the motion of a pulse– Calculate the speed of a wave

pulse– Observe standing waves– Investigate the relationship

among wave speed, wavelength, and frequency

– Make a model of wave motion– Distinguish between transverse

and longitudinal waves

• Do Now:– LO and SC reflection

• Go through what we have covered so far and write page #s next to each item

• How do you know you have met this success criteria or learning objective? On left side page

Part B Big Ideas• Speed of a

wave=distance/time• Speed=frequency x

wavelength• Frequency=#times

the wave moves up and down each second

• Energy travels in waves

• Transverse Wave:

• Standing Wave:

Investigate: Part C• Longitudinal Waves• Complete all sections, OK with

teacher

Part C Big Ideas• Compressional/Longitudinal Waves

Physics Talk• Waves Transfer

Energy

• Example

• A wave transfers energy with no transfer of mass

• When you throw a ball the mass and kinetic energy move from one place to another

• A wave transfers only energy, no mass is moving.

Physics Talk• How is energy

transferred?• Chemical energy in

musclesmechanical energy in armkinetic energy in spring

• Energy transferred from one form to another, but TOTAL energy remains the same…Conservation of Energy!

Physics Talk• How do waves

“add”?• They continue to

travel as though the other wave never existed.

• http://www.youtube.com/watch?v=Xqo6sEt1cUE

Physics Talk• Periodic Wave

• Crest

• Trough

• Amplitude

• Repetitive series of pulses

• Highest point on a periodic wave

• Lowest point on a periodic wave

• Height of crest or depth of trough

Physics Talk• How does

amplitude relate to sound?

• How does amplitude relate to energy?

• Large amplitudeLoud sound!

• Small amplitudesoft sound

• Large amplitudeLarge amount of energy

• Small amplitudesmall amount of energy

• Wavelength (λ)

• Frequency (f)

• Distance between two consecutive crests or troughs

• Symbol is λ (pronounce lambda)

• Number of waves per unit time

• Usually waves/sec called hertz (Hz)

Physics Talk• Period (T) • Time required to

complete one complete wave (crest-trough-crest)

• Period and frequency are inversely proportionate

• T=1/f• f=1/T

Physics Talk• Transverse Waves

• Compressional (Longitudinal) Wave

• The medium moves perpendicular to the direction of the wave

• The medium moves parallel to the direction of the wave

• http://www.youtube.com/watch?v=MoVz2ENJb8M

Physics Talk• Standing Wave • Wave pattern that

remains in a constant position.

• Does not go right/left, but does go up/down.

• http://www.youtube.com/watch?v=03cUrkjqdE0

• Node

• Antinode

• Place on a standing wave that is motionless

• Point on a standing wave where the displacement (movement) is greatest

• What type of wave is sound?

• Compression Wave• Air molecules get

compressed and move through the air

• How can you calculate the speed of a wave?

• Speed=Distance/Time

• Wave speed=wave frequency x wavelengthv=fλ

Sample problems on pg. 502

• Learning Objective:– Describe how waves carry

energy– Describe how wavelength,

frequency and speed of a wave are related

• Success Criteria:– Observe the motion of a pulse– Calculate the speed of a wave

pulse– Observe standing waves– Investigate the relationship

among wave speed, wavelength, and frequency

– Make a model of wave motion– Distinguish between transverse

and longitudinal waves

• Do Now:– Finish LO and SC reflection

• Go through what we have covered so far and write page #s next to each item

• How do you know you have met this success criteria or learning objective? On left side page

– Essential Questions Pg. 504• What does it mean?• How do you know?• Why should you care?

Essential Questions• Pg. 504–What does it mean?– How do you know?–Why should you care?

Vocabulary ActivityBook Definition: Definition in YOUR words

Example Picture or Equation

HW: PTG #1, 2, 5-8, pg. 505-506