Chapter 5 Module 3 Flashcards
Material that is capable of recovering its shape after a force deforms it is called
Elastic
The amount of stretching or compression of a spring is
Directly related to the force applied to it
A vibration is a
Back and forth motion that repeats itself
The equilibrium position is where a spring is
At rest and not applying a force attached
A vibrating mass and spring system will eventually come to a stop as a result of air resistance and internal
Friction
A material is elastic if it
Can recover its shape after a force deforms it
The extent a spring will compress or stretch is directly related to the
Force or pressure applied to it
If a mass is attached to a spring but the spring is not applying a force to the mass, then the spring is in its
Equilibrium position
Frequency
The number of cycles per second
Period
The number of seconds per cycles
Amplitude
The largest displacement from the equilibrium position
A mass attached to a spring is moving back and forth; the spring and mass are vibrating. What two factors will cause the motion to eventually stop?
Air resistance
Internal friction
A cycle is
One complete vibration
The unit of measurement for frequency is the
Hertz
A complete vibration occurs with a motion away from a point, to the other side of the equilibrium position, and back again to the starting point; this complete vibration is called a
Cycle
The equation for determining period (T) is
T=1/f
Mechanical waves are
Traveling vibrations in a medium
The hertz (Hz) is a measurement of __________, and one hertz is expressed in units of 1/s
Frequency
Longitudinal waves cause vibrations to occur in
A direction parallel to their own movement
The equation for determining frequency (f) is
F=1/T
A wave that causes a disturbance perpendicular to the direction of its travel is a
Transverse wave
Traveling vibrations in a medium are better known as
Waves
A medium without interaction, or attachments, between particles cannot transmit
Transverse or shear waves
A disturbance that causes particles to move closer together or farther apart in the same direction that the wave is moving is a
Longitudinal wave
Sound waves in air must be ___________ waves since air movements are not attached to their neighboring molecules
Longitudinal
A transverse wave cause a disturbance
Perpendicular to the direction of its travel
Wavelengths are measured in _________ and denoted by the Greek letter λ
Meters
The frequency of a wave can be determined by
Counting how many wave crests pass by a given point in a unit of time
Transverse and longitudinal waves require a medium for travel. The nature of the medium controls the type of waves it can transmit. The key characteristic of the medium is
If there is some interaction, or attachment, between the molecules in the medium
Wavelength
The distance between two identical points on adjacent waves
The amount of time for a wave to repeat itself
Period
Rest position
The place any undisturbed molecules would be located
Sound is transmitted in air as longitudinal waves because
Air molecules are not attached to one another and therefore cannot transmit transverse waves
The equation for velocity of a wave is
v= λf
The symbol for wavelength is
λ
Less than 20 Hz
Infrasonic
Between 20 and 20,000 Hz
Audible
Over 20,000 Hz
Ultrasonic
Counting the number of wave troughs that pass you in a given amount of time will give you the ______ of the wave
Frequency
True or False: Mammals (humans, dolphins, dogs, bats) all can hear in the same range of frequencies
False
The maximum disturbance from the undisturbed (rest) position
Wave crest
The maximum disturbance in the opposite direction from the rest position
Wave trough
The maximum displacement from the rest position
Amplitude
Tiny hairs in your inner ear respond to the _________ of the vibrations passed to them via three tiny bones in the middle ear. These bones respond to the vibrations occurring in the _________.
Frequencies; eardrum
The product of wavelength and frequency is a wave’s
Velocity
Sound waves do not travel in outer space because
Space is a vacuum, and thus there is no medium that can carry the disturbance
A substances’s ability to transmit sound waves is determined by the strength of the interaction between the ________ in a medium and their inertia
Molecules
Which of the following statements is true in regard to hearing within the animal kingdom?
Many nonhuman animals can hear sounds outside of the ranges that humans can hear
True or False: In air, light waves travel faster than sound waves
True
Human hearing works by converting the pulses of increasing and decreasing pressure as recorded in the ear into
Signals sent to the brain by nerves; these signals are interpreted as frequencies of sound with a certain pitch
What temperature of air will transmit sound waves the fastest
40 degrees Celsius
True statements of spherical waves
Small sections of spherical waves can be considered linear waves at some distance from the source; wave fronts are the same part of each wave in a spherical wave
Sound waves require a medium in which to be transmitted. This explains why sounds do not travel in
Outer space
When waves encounter different conditions, such as changes in temperatures, humidity, or nature of the material, a division referred to as a __________ occurs
Boundary
What two factors determine how well a substance can carry a sound wave
The strength of the interaction between molecules; the inertia of molecules
Refraction is the
Bending of a wave front
Sound waves are ________ than light waves
Slower
What can happen when a sound wave front strikes a boundary that is parallel to it?
Transmission
Absorption
Reflection
An increase in air temperature will __________ the speed at which sound can be transmitted through it
Increase
Different materials absorb and reflect sound waves
At different ratios of absorption and reflection
At a great enough distance from a source, a small part of a ________ wave can be considered a _________ wave front
Spherical; linear
Reverberation of sound waves involves
The mixing of reflected and original waves
Boundaries are the divisions between two physical conditions. Boundaries normally result between different materials or between
The same material with different conditions
The bending of a wave front is called
Refraction
A sound that has been reflected and can be distinguished from the original sound is called an
Echo
Sound wave fronts striking a parallel boundary may be _________, reflected, or __________
Absorbed; transmitted
Sonar is used to determine the distance to a reflective surface. The distance can be determined since the ___________ of sound waves in water is known, and the _________ it takes for the waves to return can be measured
Velocity; time
If two waves meet and are in phase, the result is ___________ interference; if two waves meet and are out of phase, the result is _________ interference
Constructive; destructive
The mixing of reflected sounds with the original sound waves is called
Reverberation
When two waves meet, the amplitude of the new wave is the
Algebraic sum of the amplitude of the two separate wave patterns
A measure of the energy a sound wave is carrying is its
Intensity
An echo is a reflected sound that can be
Distinguished from the original sound
Loudness, the subject’s interpretation of sound, is related to the
Distance between you and the vibrating source
Energy of the vibrating object
Condition of the air that the sound wave travels through
Sonar depth finding works by bouncing sound waves off the bottom of the ocean (or other body of water). The distance to the bottom is determined by _________ the distance determined from the equation d= vt
Halving
An increase of 20 on the decibel scale, for example, from 20 to 40, is equal to an increase of _______ on the intensity scale
100
If waves traveling in opposite directions meet and a wave crest from each meets at the same place and at the same time, the result is
Constructive interference
Resonance occurs when the frequency of the external forces matches the ________ frequency of the object
Natural
If two waves meet, the resulting wave’s amplitude is the sum of the two separate ___________ of the original waves
Amplitudes
Intensity is defined as the ________ transmitted by waves to a unit area (in square meters) that is perpendicular to the waves
Power
If striking a turning fork causes a nearby but unstruck turning fork to resonate, the
Two tuning forks share the same resonant frequency
If the amplitude of a wave is doubled, it will quadruple the wave’s intensity. This doubling of the wave’s amplitude will
Not quadruple the loudness
A ratio of the intensity level of a given sound to the threshold of human hearing is measured using the
Decibel scale
When the frequency of an external force matches the natural frequency of an object, the condition is called
Resonance
Reflected waves that interfere with incoming waves of the same frequency produce
Standing waves
The formation of nodes and antinodes is directly dependent on
Destructive and constructive interference
A string attached at both ends will have one frequency that can produce the longest standing wave in it; this frequency is the lowest possible frequency and is called the
Fundamental frequency
Nodes are places of __________ interference and antinodes are places of ________ interference
Destructive; constructive
From the fundamental frequency on up, those frequencies are capable of forming standing waves on a string attached at both ends are called
Overtones
Instruments that produce waveforms with overtones, whether that is from the vibration of strings or of air, are referred to as ___________ instruments
Harmonic
The Doppler effect is the
Change in pitch due to the relative motion of the source and the receiver of a sound
Mach number is the ratio of the velocity of an object to
The velocity of sound
