Unit IV - Wave Phenomena
I.
Introduction to Waves
Wave – __________________disturbance that travels
through a material or space
Ex) ____________________________________
A.
Waves and
Energy
1.
Waves
___________ ___________________from one
place to another
with no transfer of ____________
1.
Waves can be
produced in two ways:
a.
Vibration of
_______________(requires a medium for transfer)
ex) _______________________________________________
b.
Small
_______________ in the strength of an _____________
(requires ______________________________)
ex) _______________________________________________
B.
Pulses &
Periodic Waves
1.
Pulse – _____________________vibratory disturbance that
moves from point to point
a.
When the
pulse reaches a boundary with another medium, part is
______________
and part is _______________
b.
When a pulse
reaches a __________________, unyielding boundary, then
the pulse is completely ________________________________________
2.
Periodic Wave
– series of evenly timed disturbances in a medium
pulse periodic
wave
C.
Vibrations and
Waves
1.
Longitudinal
– a vibrational
disturbance which is _________________to
the direction in which the wave travels
ex) ______________(think of a guitar string)
2.
Transverse
– vibrational
disturbance which ________________________ to the direction in which the wave
travels
******** Unlike
longitudinal, transverse waves can be _______________ in many different
planes.
Ex) ______________________________________________________
II.
Characteristics
of Periodic Waves
A. Frequency - f = ____________________
How many cycles are shown
from dot to dot? ________
(one single
vibration)
Ex) 10 cycles pass a fixed point in a wave train in 5
seconds. What is the frequency of the wave?
Top view of a periodic wave (Each line is a crest)
A wave generator operating
for 4 seconds produces the waves drawn above. What is the frequency of this
periodic wave train?
How many waves are drawn?
_______ (Be careful!!)
f
= __________
·
In Sound,
frequency determines ________________.
·
In Light,
frequency determines _____________________.
The human ear can detect a
frequency between_________________________
B. Period
– time for an entire wave cycle to pass a given point in a medium
(seconds) T =
cycle Period
C. Amplitude
– maximum change in position of a particle from its rest position during a
single vibration
1.
_______________ of a wave shows the amount of __________
in the wave
a.
Amplitude is a
measure of _______________________________
_________________________________________________
D.
Phase
"In Phase"
– points on a single periodic wave that has the same displacement from the
equilibrium position, and moving in the same direction
Whole number of
wavelengths apart
A & ____
A & ____ A & ___ B
& ___ B & ___
Out of Phase "– (________) same displacement from equilibrium position but
going in a ___________direction
E.
Wavelength – ______________________________________