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Characteristics of ALL WAVES
Characteristic I
Demo I
Demo II
Observations:
Property:
Symbol:
Units:
Examples:
Relationship Between Frequency and Period
f-
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Τ-
2
Demo III
Characteristic II
Demo I
Demo II
Demo III
Observations:
Property:
Symbol:
Units:
Examples:
Characteristic III
Demo I
Demo II
Observations:
Property:
Symbol:
Units:
Examples:
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Demo III
Characteristic IV
Demo I
Demo II
Demo III
Observations:
Property:
Symbol:
Units:
Examples:
Formula for Speed:
What wave property is measured in the same units as distance?
What wave property is measured in the same units as time?
Formula for Wave Speed:
Speed of Light =
Ex 1:
Determine λ for a light wave with a frequency of 1.5x10
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Speed of Sound =
14
Hz.
Ex 2:
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Determine λ for a sound wave with a frequency of 165 Hz.
Parts of a Wave
Cycle:
One Cycle
How many cycles are represented in the diagram above?
One Cycle
Wave Pulse:
1.
2.
Traveling Wave:
3.
Q.1. A traveling wave is produced on a slinky and travels to the right as shown below. A piece of ribbon is attached to the slinky. At the time and location
shown, which way is the piece of ribbon moving?
Ribbon
Type of Wave:
# of cycles:
Motion of Ribbon:
Conclusions:
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Properties of a Pendulum
What factors did you test in the Pendulum Lab?
Factor 1
Factor 2
Effect on Period:
Factor 3
Effect on Period:
Effect on Period:
The period of a pendulum depends directly on the
The formula for the period of a pendulum:
of the pendulum.
𝑇𝑇 = 2𝜋𝜋�
𝑙𝑙
𝑔𝑔
Q.1. How long would a pendulum need to be to have a period of one hour?
Given
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Need
Relation
Solution
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Waves
AIM:
What are the main types of waves?
Several different waves were demonstrated on the spring. Based upon your observations, provide a working
definition of a wave.
What actually moved along the spring (what was transferred by a wave)?
There are two main families of waves:
Mechanical
Electromagnetic
What is a medium?
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Mechanical Wave Type I
Mechanical Wave Type II
Sketch:
Sketch:
Observations:
Observations:
Direction of Medium (Spring):
Direction of Medium (Spring):
Direction of Wave:
Direction of Wave:
Name:
Name:
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Q.1. Identify each type of mechanical wave is shown below?
A
A sound wave
B
C
Wave on a srping
D
A light wave
Water Ripples
E
F
Air in tube
Earthquake Waves:
P-Waves:
S-Waves:
Conclusions:
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When Waves Overlap
A - Waves in Phase
B – Waves Out of Phase
Observations:
Observations:
B
Groupings:
AE
BF
CG
DH
EI
A
What other points are in phase with point A?
F
C
I
G
M
K
E
D
H
What points are ½λ out of phase with A?
Conclusions:
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J
10
L
What points are ¼λ out of phase with A?
Waves at Boundaries
Soft Reflection
Hard Reflection
Observations:
Observations:
Reflections of:
Sound
Light
Other E&M Waves
Conclusions:
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Superposition & Interference
Waves travel on a string as shown. Show how the string looks when the waves cross each other in region X-----Y, and after the collision.
Before
During
Case I
1
After
Resulting
Pulse
B
A
-1
x
y
x
y
B
x
A +B
y
A
x
y
Case II
1
A
-1
B
x
y
x
y
x
y
x
y
x
y
x
y
Case III
1
B
A
-1
x
y
Case IV
1
A
-1
B
x
y
Superposition:
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Q.1. Which cases showed waves adding and forming a bigger wave?
Term:
Q.2. Which cases showed waves adding and forming a smaller (or no) wave?
Term:
Q.3. Add the following transverse and longitudinal waves and determine if the interference is constructive or destructive.
1
2
5
5
CA
AA
B
Type of Wave
F
+
Constructive Interference
Wave on Spring
Light Wave
Sound Wave
Conclusions:
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E
D
3
5
Examples:
3
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Destructive Interference
Standing Waves & Superposition
Demo I
Demo II
Observations:
Observations:
Pulse:
Standing Wave:
Nodes & Antinodes
4m
Node:
Antinode:
Q.1. Determine the following for each diagram below: wavelength, # of nodes and antinodes, and frequency (for a given wave speed of 10 m/s).
4m
A
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4m
4m
B
C
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