Review Questions
on pgs. 387-388
1a. What is a "wiggle" in time called?
A "wiggle" in time is called a vibration (a repeated,
back-and-forth movement around a midpoint).
1b. What is a "wiggle" in time and space called?
A "wiggle" in time and space is called a wave (a
regularly, repeated, back-and-forth movement that
travels through a substance without taking that
substance with it).
2.
What is the period of a pendulum?
A "wiggle" in time is called a vibration (a repeated,
back-and-forth movement around a midpoint).
3.
What is the period of a pendulum that takes 1 s to
make a complete back-and-forth vibration?
If 1 complete back-and-forth swing takes 1 s, then
the period of the pendulum is 1 s.
4.
Suppose that a pendulum has a period of 1.5 s. How
long does it take to make a complete back-and-forth
vibration?
If 1 complete back-and-forth swing takes 1.5 s,
then the period of the pendulum is 1.5 s.
Is this 1.5 s period shorter or longer than a 1 s
period pendulum?
A 1.5 s period is longer than a 1 s period.
Review Questions
on pgs. 387-388
7. Distinguish between the period and frequency of a
vibration or a wave. How do they relate to each other?
Period (T) is the time it takes for one cycle to occur.
Frequency ( f )is how often a cycle occurs. Period and
frequency are inverses or reciprocals of each other.
T = 1/ f and f = 1/T
8. Does the medium (matter) in which the wave travels
move along with the wave itself? Defend your answer.
No, a wave does not move the matter it is traveling
through with it as it moves. For example, when an
audience at a sporting event starts the "wave" the
people stand up and then sit down as the "wave"
travels around the stadium, they don't move around
the stadium with the "wave."
9. How does the speed of the wave relate to its
frequency and wavelength?
Wave speed is determined by the product of the
wavelength (distance between two corresponding
locations on the wave) and the frequency (how often
the wave cycle occurs).
vWAVE = λ x f
10. As frequency of sound increases, does the
wavelength increase or decrease? Give an example.
As frequency (# of cycles per time) increases the
distance between the waves (wavelengths) will
decrease because more waves are occurring in the
same amount of time.