A Home Brewed Worksheet:
Sections 13.1 through 13.6
(for my Conceptual Physics students)
Section 13.1
A vibration is a wiggle. When the wiggle moves through space and time
it is a ____________. Light and ________ are both __________
that move through space as _____________. Sound is the movement
of ___________ of ___________. ________ cannot travel through
a ___________, but __________ can. Light is a vibration of
__________ and ______________. The shape of a simple wave is
called a ___________ curve. The high points of a wave are called the
______________ and the low points are called the ____________.
The ___________ is the distance from the midpoint of the vibration
to the crest or ___________. The ___________ is the distance
from one crest to the next one. The __________________ of any
vibrating object is the number of to-and-fro vibrations the object is
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the number of to-and-fro vibrations the object makes in a given time
(usually ______________). The unit of frequency is the
____________. AM radio waves have __________ frequencies than
FM radio waves. Radio waves are caused by the vibration of the
____________ in the broadcasting antenna. The
________________ of a wave or vibration is the time for a complete
_____________. Period can be found from the frequency using the
equation:
A bowling ball swings back and forth in 2.0 seconds. Its frequency is
_________ Hertz.
Section 13.2
A wave is a method of transferring _____________ from one place to
another. A water wave, for example, transfers energy from far out at
sea to the shore. The water itself, however, goes ____________.
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When you speak the __________ of your _________ travels at the
speed of sound across the room. This speed is equal to around
___________m/s. There are two ways to find the speed of a wave.
The first way is to divide ____________ by time. Fig. 1 illustrates
this equation:
Fig. 1. Speed Equation
The second way is to divide the _________ by the period. Since
period is equal to the reciprocal of the __________ we can also find
the
speed
by
multiplying
the
wavelength
by
the____________________. For example, light, which has a constant
speed, has a ___________ frequency when its ____________ is
short and a _____________ frequency when its ___________ long.
Red light has a ____________ frequency, but a _____________
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wavelength and violet light has a ____________ frequency, but a
_____________ wavelength.
Section 13.3
Waves can vibrate two different ways. One way is called
_______________. With this type, the _________ of the source is
perpendicular to the direction of wave travel. Waves in a stretched
string and _____________ waves are transverse waves. The source of
sound waves vibrates _________________ which means the vibration
of the source is parallel to the direction of ______________. A
longitudinal wave in a Slinky, for example, has regions of
_____________ and _______________. The distance between
neighboring compressions in the Slinky is called a ______________.
Section 13.4
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When a tuning fork is struck the tuning fork’s prongs vibrate to and
fro which cause the air molecules to vibrate to and fro. The air
particles will vibrate in rhythm to the prongs. Vibrations made up of
__________ and _____________ spread from the tuning fork
throughout the air. A __________ is produced. Like the last fill-inthe-blank sentence in section 13.3, the distance between neighboring
compressions of air particles is called a ______________.
A speaker changes __________into sound waves. The electrical
signals pass through a __________ wound around the neck of a
____________. This coil acts as an _____________ which is located
near a _________________. ____________ in the electrical signal
cause the __________ to vibrate which in turn produces
___________.
The speed of sound in air at 0o C is about ____________ meters per
second. Sound’s speed increases by 0.6 meters per second for each
degree rise in temperature above 0o C. So at room temperature, which
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is 20o C, sound travels at _____________ meters per second.
Assuming the temperature to be 20o C, the approximate distance of a
thunderstorm when you note a 4 second delay between the flash of
lightning and the sound of thunder is ___________. Show your work
“at the board” shown in Fig. 2.
Fig. 2. Show your work at this board.
Sound travels fastest in ____________ and slowest in
_____________.
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Section 13.5
The reflection of sound is called an ____________. A dolphin senses
distance by noting the ___________ between sending sound and
receiving its ____________. A dolphin senses direction by noting the
differences in _______ for the echo to reach its _______ ears.
Sound reflects from a smooth surface the same way that
___________ does: The angle of ___________ is equal to the angle
of ___________. In opera halls reflective surfaces are sometimes
placed on the ceiling to direct sound to the audience. A listener looking
up at the surface can ___________ the reflected images of the
members of the orhestra. Both _________ and __________ obey the
same law of _____________.
Section 13.6
The bending of waves around a barrier is called ______________.
The greater the wavelength the more likely the wave will bend around a
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barrier. For example, Fig. 3 shows a girl named Penelope standing
behind a boy named Freebus. You can’t see her face, but when she
speaks, you can hear her voice. This is evidence that sound has a
wavelength which is ____________than light waves.
Fig. 3. Penelope while speaking is standing behind Freebus
Fig. 4 shows two possible designs for a fog horn which sends sound out
to sea to warn ships of a rocky shore. Which design is best? Answer:
__________
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Fig. 4. Two fog horn designs. Which one (A or B) is best?
Some animals use echos to locate objects. _________ and
___________ are examples. Name two more animals that use echos.
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