Physics 8.1 (Vibrations and waves)
____________ the amplitude of a wave increases the amount of energy that wave transfers each second by a factor of _______.
Doubling --- 4
______________ is a transverse wave.
Light
_________________ require a medium, such as water, air, ropes, or a spring.
Mechanical waves
How are waves reflected and refracted at boundaries between mediums?
Reflection of a light wave involves the bouncing of a light wave off the boundary, while refraction of a light waveinvolves the bending of the path of a light wave upon crossing a boundary and entering a new medium. ... The refractedray is the ray that points in the direction that the refracted waves are traveling.
_____________ waves are longitudinal waves.
Sound
What is the relationship between wave speed, wavelength, and frequency?
Wave speed is the distance a wave travels in a given amount of time, such as the number of meters it travels per second. Wave speed is related to wavelength and wave frequency by the equation: Speed = Wavelength x Frequency. This equation can be used to calculate wave speed when wavelength and frequency are known.
How does the principle of superposition apply to the phenomenon of interference?
When two waves interact, the principle of superposition says that the resulting wave function is the sum of the two individual wave functions. This phenomenon is generally described as interference. ... If there's a single drop hitting the water, it will create a circular wave of ripples across the water.
The ___________ of periodic motion is the greatest distance from equilibrium.
amplitude
A point that has the largest displacement is called an __________________.
antinode
Waves that are deep in a lake or ocean are longitudinal; at the surface of the water, however, the particles move in a direction that is ___________________ to the direction of wave motion, as shown in the figure below.
both parallel and perpendicular
When you throw a small stone into a calm pool of water, you see the _______________________ of the resulting waves spreading out in all directions.
circular crests and troughs
When waves __________________, they can cancel or form a new wave of lesser or greater amplitude.
combine
Each high point of a wave is called a _____________.
crest
A wavefront is a line that represents the ___________________ in two dimensions, and it can be used to show waves of any shape, including circular waves and straight waves.
crest of a wave
As the waves move from deep to shallow water, their speed _______________, and the direction of the waves ____________.
decreases --- changes
If you record the motion of a single particle, that motion can be plotted on a ________________________. The period can be found using the time axis of the graph.
displacement-versus-time graph
The _______________ of a wave (f) is the number of complete oscillations it makes each second.
frequency
A ripple tank can also model the behavior of waves as they travel ____________________.
from one medium into another
Frequency is measured in ___________. One hertz (Hz) is one oscillation per second.
hertz
How do transverse and longitudinal waves compare?
in transverse waves, the displacement of the medium is perpendicular to the direction the waves travels. In longitudinal waves, the displacement is parallel to the direction the waves travel.
The wave that strikes the boundary is called the ____________.
incident wave
Waves can __________ with other waves.
interfere
The result of the superposition of two or more waves is called ________________.
interference
The frequency and period of a wave are _______________.
inversely related
A ____________________ is one that vibrates parallel to the direction of the wave's travel.
longitudinal wave
Waves transfer energy without transferring ____________.
matter
For most mechanical waves (except water surface waves) the speed depends only on the ___________ through which the waves move.
medium
Waves with greater amplitudes transfer ________________.
more energy
A point that does not move is called a ___________.
node
A rigid barrier placed in the ripple tank will reflect waves. This can be modeled by a ray diagram. The orientation of the barrier is shown by a line, called the _____________, which is drawn ______________ to the barrier.
normal --- perpendicular
Because the waves in the shallow water are generated by the waves in the deep water, their frequency is ___________.
not changed
Crests are spaced by __________ wavelength. Each trough is also one ___________ from the next.
one --- wavelength
The ______________ of a wave is the time is takes a point to complete a complete cycle.
period
If the disturbances continue at a constant rate, a _________________ is generated.
periodic wave
Since amplitude is a distance, it is always ___________.
positive
The ___________________________ states that the displacement of a medium caused by two or more waves is the algebraic sum of the displacements caused by the individual waves.
principle of superposition
When a wave encounters the boundary of the medium in which it is traveling (reaches the end), some or all of the wave can...........
reflect back into the medium pass through the boundary into another medium, often changing direction at the boundary
A rigid barrier placed in the ripple tank will ______________. This can be modeled by a _____________.
reflect waves --- ray diagram
If some of the energy of the incident wave is reflected backward, the returning wave is called the ____________________.
reflected wave
The change in the direction of waves at the boundary between two different media is known as ___________.
refraction
The wavelength, wavespeed, and the frequency are _________.
related
A ______________ can be used to show the properties of two-dimensional waves. Vibrating boards produce waves with long straight wavefronts.
ripple tank
For waves that move at the _______________, the rate at which energy is transferred is proportional to the square of the amplitude.
same speed
Based on the equation λ = v/f, the decrease in the speed of the waves means that the wavelength is __________ in the shallower water.
shorter
Both the period and the frequency of a wave depend only on its _____________. They do not depend on the wave's speed or the medium.
source
The _____________ of a wave is the distance that one of the wave's crests or compressions travels divided by the time interval.
speed
A _________________ is a wave that appears to be standing still, produced by the inference of two travel waves moving in opposite directions.
standing wave
Each of the waves is a ______________, which has characteristics of both transverse and longitudinal waves.
surface wave
A ripple tank can also model the behavior of waves as they travel from one medium into another. For example,________________________________________.
the water in one part of the tank might be shallower than the water in the rest of the tank. This shallow water acts like a different medium
A ________________ is one that vibrates perpendicular to the direction of the wave's motion.
transverse wave
A _______________________ is the maximum distance of the wave from equilibrium.
transverse wave's amplitude
Each low point of a wave is called a ___________.
trough
If some of the energy of the incident wave is reflected backward, the returning wave is called the reflected wave. Whether the reflected wave is upright or inverted depends on the characteristics of the ______________.
two mediums
A ___________ is a disturbance that carries energy through matter or space.
wave
When you throw a small stone into a calm pool of water, you see the circular crests and troughs of the resulting waves spreading out in all directions. You can sketch those waves by drawing circles to represent the _______________.
wave crests
A _____________ is a single bump or disturbance that travels through a medium.
wave pulse
If you dip your finger into water with a constant frequency, the resulting sketch would be a series of concentric circles, called ______________, centered on your finger.
wavefronts
The shortest distance between points where the wave pattern repeats itself is called the _________________.
wavelength (λ)
What are waves?
waves are energy in motion