Unit 9: Let Us
Entertain You
Essential Questions
 What are the relationships among wavelength,
frequency, and speed of a wave?
 How are vibrations and pitch varied in a string to
produce different sounds?
 How does vibrating air produce sound?
 How do plane and curved mirrors affect the
image that is produced?
 How can the colour of an object appear to be
different by shining different colour light on it?
Chapter Challenge
 You will work with your partner to create a 2-4
minute light and sound show
 This can be performed “live” or shown as a video
 Along with it, there will be a written report that
explains the physics concepts used in the show
and explains why each concept is important
 The sound must come from instruments or noise
makers you make yourself
 Due date: Monday, June 3 (During exam time)
Day 1: Making Waves
 Learning Objectives:
 Observe the motion of a pulse
 Measure the speed of a wave
 Observe standing waves
 Investigate the relationship among
wave speed, wavelength, and
frequency
 Make a model of wave motion
Starter
 Tsunamis are giant ocean waves caused by an
underwater earthquake
 Waves can reach extremely high heights, for
example in Thailand (2004), the waves reached
30m
 How does water move to make a wave?
 How does a wave travel?
 Time: 10 minutes
Video: Japan Earthquake
Activity 1
 Draw a picture of a wave that includes the
following terms:
 Amplitude
 Wavelength
 Crest
 Trough
 Time: 15 minutes
Activity 2
 For you to do, pg. 327
 Steps #1-10
 Write down observations, record data
 Data table will be provided for you
 Make a concluding statement about the
relationship of frequency, wavelength and speed
of a wave
 Time: 45 minutes
Activity 3
 Discussion of results and conclusion
 Draw a picture that shows what happens to the
frequency of a wave if you increase or decrease
the wavelength
 Time: 10 minutes
Homework
 For you to read, pg. 331
 Physics talk, pg. 333
 Physics to go, pg. 337 #1, 7, 10, 11, 12
Day 2: Sounds in Strings
 Learning Objectives:
 Observe the effect of string length and tension upon
pitch produced
 Control the variables of tension and length
 Summarize experimental results
 Calculate wavelength of a standing wave
 Organize data in a table
Starter
 When the ancient Greeks made stringed musical
instruments, they discovered that cutting the
length of the string by half or two-thirds produced
other pleasing sounds.
 How do guitarists or violinists today make different
sounds?
 Time: 10 minutes
Video: The Physics of Sound
Activity 1
 For you to do, pg. 340 in lab groups
 Steps #1-7
 Record the data table and answer the
questions/observations to go along with the steps
 Hand in 1/lab group at the end of the period
 All equipment is on back table
 Time: 45 minutes
Activity 2
 Physics to go, pg. 344 #7
 There are wood blocks in the back storage area that have
strings on them
 Work with your lab group to produce different sounds and
answer the following:
 Explain how different sounds are being produced using
wavelength, frequency, pitch, and standing waves in your
explanation
 Describe how the instrument works using wavelength, frequency,
and standing waves in your description
 Hand in with the “for you to do” activity
 Time: 20 minutes
Homework
 Please take your roller coaster models home
 For you to read, pg. 343
 Physics to go, pg. 344 #1, 2, 3
Day 3: Sounds from
Vibrating Air
 Learning Objective:
 Identify resonance in different kinds of tubes
 Observe how resonance pitch changes with length
of tube
 Observe the effect of closing one end of the tube
 Summarize experimental results
 Relate pitch observations to drawings of standing
waves
 Organize observations to find a pattern
Starter
 The longest organ pipes are about 11m long. A
flute, is about 0.5m long and makes musical
sound in the same way.
 How do a flute an organ pipes make sound?
 Time: 15 minutes
Video: Sound in pipes
Video: Fresh Prince
 Season 1, Episode 1
 Time: 13:51
Activity 1
 For you to do, pg. 347 Steps 1-3
 Data table is provided for you
 Write a concluding statement about straw length
and the pitch obtained
 Time: 20 minutes
Activity 2
 For you to do, pg. 347, steps 4-5
 Write a concluding statement about the amount
of water in the test tube and the sound you hear.
 How can this be changed to use in your sound
and light show? (i.e. what materials could you
use?)
 Time: 20 minutes
Activity 3
 Create an “instrument” that uses at least one of
the principles that we have discussed thus far
 Wavelength
 Frequency
 Pitch
 Create an advertisement that tries to sell your
instrument to the rest of the class
 Time: 30 minutes
Homework
 Physics Talk, pg. 348
 For you to read, pg. 349
 Physics to go, pg. 351 #1, 2, 3, 4
Day 4: Reflected Light (60
min)
 Learning Objectives:
 Identify the normal of a mirror
 Measure angles of incidence and reflection
 Observe the relationship between the angle of
incidence and the angle of reflection
 Observe changes in the reflections of letters
 Identify patterns in multiple reflections
Starter
 Astronauts placed a mirror on the moon in 1969
so that a light beam sent from Earth could be
reflected back to Earth. By timing the return of
the beam, scientists found the distance between
Earth and the Moon. They measured within 30cm.
 How are you able to see yourself in a mirror?
 If you want to see more of yourself, what can you
do?
 What type of image is produced?
 Time: 10 minutes
Video: How do Mirrors
Work?
Activity 1
 You and your lab group are to design a short
video clip to be posted on Youtube
 This clip needs to explain to students how plane
mirrors work
 Use your text book and/or internet to help you
 Think about how to present your video in a fun
and meaningful way (i.e. think about what type
of video you would want to see)
 Time: 30 minutes
Activity 2
 Present your clips to the class
Homework
 For you to read, pg. 357
 Physics to go, pg. 359 #1, 2, 4, 5,
Day 5: Curved Mirrors
 Learning Objectives:
 Identify the focus and focal length of a curved mirror
 Observe virtual images in a convex mirror
 Observe real and virtual images in a concave mirror
 Measure and graph image distance vs. object
distance for a convex mirror
 Summarize observations in a sentence
Starter
 Curved mirrors can be concave or convex
 Draw a picture of what these two types of mirrors
look like
 Where do you find concave and convex mirrors?
 How are the images produced different from
that of a plane mirror?
 Time: 15 minutes
Video: Curved Mirrors
Activity 1
 With your lab group, complete the table
 Time: 15 minutes
Type of Mirror
Plane
Concave
Convex
Image Upside
Down/Rightside
Up
Real/Virtual
Image
Size of Image
Activity 2
 Draw a ray diagram for the following types of
mirrors:
 Plane mirror
 Concave mirror, image in front of focal point
 Concave mirror, image behind focal point
 Convex mirror
 We will do one together first
 Time: 20 minutes
Plane Mirror
Convex Mirror
Concave Mirror
Activity 3
 Use this time to create a concept map for the
various topics we have covered so far
 This will be useful when you are writing the
explanation component of your chapter
challenge
 It is a good idea for everyone to have one of
their own
 Time: 15 minutes
Homework
 Physics Talk, pg. 366
 Reflecting on the Activity and the Challenge, pg.
377
 Complete concept map
 Physics to Go, pg. 367 #1, 2, 3, 4
Day 6: Refraction of Light
 Learning Objectives:
Day 7: Colour