1. PHYSICS 1 The Nature of
Waves

2. Forth and
VIBRATIONS AND WAVES Back

3. VIBRATIONS OF A PENDULUM
 Vibration
 Wiggles in TIME
 Swings forth and back
 By its nature, it wiggles
 Galileo Galilei
 Pisa Cathedral; chandelier
 Isochronism of the pendulum
 Length and Mass
 Length affects the number of swings
 Mass does not affect the number of swings

4. “The crests
and
PARTS OF A WAVE troughs of
the sea of
life that
flows”

5. WAVE DIAGRAM
Wave Length
Amplitude
Crest
Equilibrium
Trough

6. PARTS OF A WAVE
 Crest
 Highest point away from the equilibrium
 Trough
 Lowest point away from the equilibrium
 Amplitude [ A ]
 Size of the maximum disturbance away from the equilibrium
 Distance from the equilibrium to the crest or trough
 Wavelength [ λ ]
 One cycle from the equilibrium
 Distance between one full crest to one full trough
 Minimum distance for a wave to repeat itself
 Distance between two successive, identical parts of the wave

7. PERIOD AND FREQUENCY


8. PROPAGATION OF Wave
Motion
WAVES

9. ENERGY TRANSFER
 Mass and energy are
transferred
 Energy is transferred but
not mass
 A continuous production of
pulses creates a wave

10. CHARACTERISTICS OF WAVES
1. A wave transfers energy
2. A wave does not transfer matter from one place to another
3. A wave transmits information
1.5
1
0.5
0
210
75
90
315
0
15
30
45
60
105
120
150
195
225
255
285
300
330
345
360
165
240
270
180
135
-0.5
-1
-1.5

11. T YPES OF WAVES
 Mechanical Wave
 Waves that need a medium
to travel
 Electromagnetic Waves
 Waves that do not need a
medium to travel
 Medium
 Material used for energy to
travel
 Can be solid liquid or gas

12. T YPES OF WAVES
 Longitudinal Waves
 a wave who’s direction
of propagation is
parallel to the direction
of vibration
 Transverse Waves
 a wave who’s direction
of propagation is
perpendicular to the
direction of vibration
 A longitudinal wave
can be represented as
a transverse wave and
vice versa

13. Frequency
WAVE SPEED and
Wavelength

14. INTRODUCTION


15. WAVE EQUATION


16. In Phase
PARTICLE MOVEMENT and Out of
Pase

17. DEFINITIONS
 Wave Motion
 Transfer of energy from the source to a distant receiver without the
transfer of matter.
 Precise Definition for Wavelength
 A wavelength is the distance between two successive particles
vibrating in phase
 Phase of the Wave
 The motion, direction and position of a particle within the wave
sequence

18. PHASE
 In Phase
 Particles have the same displacement and are moving in the same
direction
 Particles that are an integral number of wavelengths apart are
vibrating in phase
 Out of Phase
 Particles that have opposite displacement and are moving in
opposite directions
 Particles in one wavelength have the same frequency and
amplitude but there is a phase lead from one particle to the
next
 Particles that are a half of a wavelength or a half plus an
integral amount of wavelengths are exactly or totally out of
phase