chapters 13-14 Flashcards
simple harmonic motions
the motion that occurs when the force pushing or pulling on an object is proportional to the displacement from the equilibrium
amplitude (SHM)
the maximum displacement from the equilibrium position reached by an object undergoing SHM
Period (SHM)
the time for an object to complete one entire vibration
frequency (SHM)
the number of vibrations made per second
what does the period of oscillation depend on for a spring undergoing SHM
mass and spring constant k
Is energy conserved when dealing with a mass on spring?
yes
at maximum energy what does the spring have?
elastic potential energy
at equilibrium what does the spring system have?
kinetic energy
When will the mass be traveling the fastest?
as it passes equilibrium
what does the period of oscillation depend on for a pendulum?
length of pendulum and acceleration
is energy conserved when dealing with a simple pendulum?
Yes
at its maximum amplitude what does a pendulum have?
gravitational potential energy
at equilibrium what does a pendulum system have?
kinetic energy
when will a pendulum be traveling at its fastest speed?
when it passes equilibrium
what type of graph does an object that undergoes SHM make?
in the shape of a sine or cosine function
what happens when energy is lost from a system that is undergoing SHM?
it undergoes damping
critical damping
where the oscillator returns as quickly as possible to equilibriumm
under damping
where the oscillator has a solo decrease in oscillations as it returns to equilibrium
over damping
where the damping is so large it takes a while to return to equilibrium
when energy is put into a system to cause oscillations it is said to be…
driven
if a system is not driver nor damped it will…
oscillate at its natural frequency
a system driven close to its natural frequency will experience…
large amplitude of oscillation
when is a system said to be in resonance
when its driven close to its natural frequency and has large amplitudes of oscillation
wave
a disturbance that propagates from place to place
as a wave travels it carries
energy
the amount of energy a wave can carry is determined on its…
amplitude
crest
high point of a wave
troughs
low points on a wave
wavelength
distance between identical parts of the wave
amplitude
the distance from the midpoint to the crest or trough
frequency (waves)
the number of waves to pass a position in a second
period (waves)
the time it takes for one wavelength to pass a position
transverse waves are created when
particles in a wave oscillate at right angles to the direction of the waves propagation (ex: light waves or on a stringed instrument)
longitudinal waves are created when
particles in a wave oscillate parallel to the direction of the waves propagation (ex: sound waves)
in longitudinal waves source + coils moves ___ where in transverse waves the source + coils moves ___
left and right; up and down
mechanical waves
waves that require a medium to travel in (sound waves)
speed of mechanical waves depends on what?
medium it is in
electromagnetic waves
are waves that do not require a medium to travel in and whose speed is constant (ex: light waves)
whenever a wave changes materials its frequency…
remains the same but the speed and wavelength change
when a wave is reflected from a FIXED end…
the amplitude changes because the opposing force at the fixed end acts in the opposite direction of the original amplitude
when a wave is reflected from a LOOSE end…
the amplitude direction does not change because there’s no opposing force
interference
occurs when waves arrive at the same point at the same time and combine
what does interference create
a resultant wave that is the sum of the individual wave amplitudes which is called superposition
constructive interference
occurs when the crest of one wave overlaps with the crest of another which results in a wave of larger amplitude
destructive interference
occurs when the crest of one wave overlaps with the trough of another which results in a wave of reduced amplitude
what do two waves of slightly different frequencies who interfere make
beats
beat frequency
the absolute value of the difference between the frequencies of the two waves
standing wave
a wave that oscillates in a fixed location which are results of incident and reflecting waves that are confined to a region
nodes
the point on a standing sound wave that occurs due to destructive interference, lowest amplitude
antinodes
the point on a standing sound wave that occurs due to constructive interference, the highest amplitude
increase in tension will …
increase the frequency of a standing wave on a string
standing sound wave can form…
inside a pipe with an open or closed end
in a pipe with an open end and a closed end a standing sound wave must have…
a node at the closed end and an antinode at the open end
in a pipe with two open ends a standing sound wave must have…
an antinode at both open ends (no sound will be heard at the node and a louder sound will be heard at the antinode)
what is the order of harmonics in a closed ended pipe?
1,3,5,7…
what is the order of harmonics in an open ended pipe?
1,2,3,4…
hearing
perception of sound
pitch
the frequency of the corresponding sound wave
sound consists of
longitudinal waves consisting of alternating regions of high and low pressures
what does the speed of sound depend on?
the medium and the temperature. the stiffer the medium the faster the speed, the higher the temp the faster the speed
what does the loudness of a sound depend on?
intensity of a wave
intensity
the amount of energy passing thorugh a given area in a given time or the power per area
the greater the amplitude the ____ the intensity of a wave
greater
intensity ___ with distance from the source
decreases
sound level intensity
tells you the level of a sound relative to a fixed standard
threshold of hearing
10^-12 W/m^2 or 0 dB
threshold of pain
1 W/m^2 or 120 dB
when you double the loudness of a sound you increase its intensity by a factor of …
10 which corresponds to an increase of 10 dB
doppler effect
when a wave source is moving relative to an observer. it describes what happens to the frequency of a sound as it approaches or moves away from an observer
as a sound wave approaches the observer hears a …..
higher pitch
as the sound wave moves away an observes hears a …
lower pitch
the doppler effect is NOT related to the …
amplitude or intensity of a sound wave
for a stationary observer and a moving sound source the equation is…
fsource/(1+- vsource/vsound)
+ = as source moves away
- = as source approcahes
for a moving observer and a stationary sound source the equation is…
fsource(1+- vobs/vsound)
+ = as observer approaches source
- = as observer moves away
