Overview
Waves are a disturbance through a medium caused by a source that transfers energy.
Wave Investigations
There are two different types of waves-
Mechanical Waves- Waves that need a medium.
Electromagnetic Waves- Waves that don't need a medium. We won't be looking into this type of wave since the unit is called Mechanical Waves.
The two types of Mechanical Waves are Transverse and Longitudinal Waves. Transverse waves have oscillation that is perpendicular of the motion and one of the ways that I found helpful in remembering that is that the top of the letter 'T' is perpendicular to the body of the 'T'. These waves include rope waves and light. Longitudinal Waves are waves in which the oscillation is parallel to the movement. These waves include sound and pressure waves.
Mechanical Waves- Waves that need a medium.
Electromagnetic Waves- Waves that don't need a medium. We won't be looking into this type of wave since the unit is called Mechanical Waves.
The two types of Mechanical Waves are Transverse and Longitudinal Waves. Transverse waves have oscillation that is perpendicular of the motion and one of the ways that I found helpful in remembering that is that the top of the letter 'T' is perpendicular to the body of the 'T'. These waves include rope waves and light. Longitudinal Waves are waves in which the oscillation is parallel to the movement. These waves include sound and pressure waves.
Wave Speed
Wave is determined by the medium that the wave is traveling through. It is NOT determined by the wavelength or frequency. The speed of a wave is a constant in that medium and the only way to change the wave speed is to change the medium that it travels through.
This is the wave speed formula and shows the inverse relationship between the frequency and wavelength. That means that as one gets bigger than the other gets smaller.
So if we doubled the frequency then we would have to halve the wavelength since the velocity is a constant.
https://www.google.com/search?q=wave+speed+formula&source=lnms&tbm=isch&sa=X&ved=0ahUKEwjOvbj80bbhAhWExFkKHccZAFcQ_AUIDigB&biw=1440&bih=788#imgrc=OW3f5O80XXVVyM:
So if we doubled the frequency then we would have to halve the wavelength since the velocity is a constant.
https://www.google.com/search?q=wave+speed+formula&source=lnms&tbm=isch&sa=X&ved=0ahUKEwjOvbj80bbhAhWExFkKHccZAFcQ_AUIDigB&biw=1440&bih=788#imgrc=OW3f5O80XXVVyM:
Wave Properties
Waves have different parts that include the Amplitude, the Period, the Frequency and the Wavelength.
Amplitude- The maximum Displacement of Oscillations for a wave. For a longitudinal wave it is the density of the compression and for a transverse wave it is the maximum distance from equilibrium just like for Simple Harmonic Motion. The amplitude determines the energy that a wave carries. Therefore, the higher amplitude the more energy that the wave is transferring.
Period- This is just the time between oscillations of a wave. It also equals 1/Frequency
Frequency- The number of oscillations in one second. It is measured in Hz. This is also equal to 1/Period
Wavelength- This is the distance between oscillations. Not to be confused with the period which is the time between oscillations. For a transverse wave the wavelength is the distance between crest to trough (the high point to the low point of the wave) and for a longitudinal wave it is the distance between compressions.
Amplitude- The maximum Displacement of Oscillations for a wave. For a longitudinal wave it is the density of the compression and for a transverse wave it is the maximum distance from equilibrium just like for Simple Harmonic Motion. The amplitude determines the energy that a wave carries. Therefore, the higher amplitude the more energy that the wave is transferring.
Period- This is just the time between oscillations of a wave. It also equals 1/Frequency
Frequency- The number of oscillations in one second. It is measured in Hz. This is also equal to 1/Period
Wavelength- This is the distance between oscillations. Not to be confused with the period which is the time between oscillations. For a transverse wave the wavelength is the distance between crest to trough (the high point to the low point of the wave) and for a longitudinal wave it is the distance between compressions.
This is a video by Bozeman Science that helped me understand the concept and I hope it helps you as well.
Superposition of Waves
Wave superposition is when two waves are traveling through the same medium at the same time. The waves pass through each other and then move on undisturbed by one another. While they are interacting with each other they add the amplitudes of the waves which can either be constructive or deconstructive
Constructive Interference: When the phases line up and therefore the amplitudes are aded positively which makes for a bigger amplitude.
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Deconstructive Interference- When the phase does not line up (trough and crest line up) so they add negatively to make a smaller amplitude.
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The Doppler Effect- This is a special case when the wave source is moving relative to the observer. When it is moving closer to the observer the frequency is higher due to there being a smaller wavelength which will lead to a higher pitch. When the source is moving away from the object there will be a lower frequency due to the longer wavelength and leads to a lower pitch. This video will help with the explanation of the topic.
Medium Boundaries
The Medium Boundary is just when the medium ends and therefore where the wave ends.
Fixed on both ends- Nodes on each end of the medium like string instruments
Open on both ends- Where there are antinodes on each end like a flute or other wind instruments
Open on one end and closed on the other- This is where there is a node on one end and an antinode on the other such as a tuba. This causes there to be no reflection back of the wave.
This video will describe the Ruben's Tube.
Fixed on both ends- Nodes on each end of the medium like string instruments
Open on both ends- Where there are antinodes on each end like a flute or other wind instruments
Open on one end and closed on the other- This is where there is a node on one end and an antinode on the other such as a tuba. This causes there to be no reflection back of the wave.
This video will describe the Ruben's Tube.
Standing Waves
Standing waves are the simplest a wave can be. They have a single wave that goes down on one end and then reflects and inverts and then comes back to the source. They have nodes at each end of the medium and nowhere else within the wave. They also have a wavelength that is two times the length of the medium that it is transferring energy on. The frequency of a standing wave is called the fundamental frequency and it is the frequency that causes the simplest possible wave.
Nodes- A point where there is no movement in the wave.
Antinodes- Points where there are movements in the wave.
Nodes- A point where there is no movement in the wave.
Antinodes- Points where there are movements in the wave.
This is a standing wave since it has only antinodes in between the two ends of the medium.
Waves also have these things that are called harmonics when the wave is not at its simplest form. When it has more nodes than just at the beginning and end of the medium. This video of me with a guitar will help show what exactly a harmonic is.
Speed of Standing Waves
The speed of a standing wave depends on the medium that it travels through. The equation that goes along with this is shown in the image to the left. This shows that velocity is related inversely to the linear density of the medium.
https://slideplayer.com/slide/2528858/
https://slideplayer.com/slide/2528858/
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