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8 Cards in this Set
- Front
- Back
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Displacement
Amplitude Wavelength Period Frequency Phase difference |
How far a point has moved from its undisturbed position.
Maximum Displacement. The Length of one whole wave, from crest to crest. The time take for a whole vibration. The number of vibrations per second passing a given point. The amount by which one wave lags behind another wave (measured in degrees or radians). |
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Reflection
Refraction |
The wave is bounced back when it hits a boundary.
The wave changes direction as it enters a different medium. |
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Transverse Waves
Longitudinal Waves Polarised Waves |
The vibrations are at right angles (perpendicular) to the direction of travel.
The vibrations are along the direction (parallel) of wave travel. They only oscillate in one direction. |
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Siren Moving Towards Observer
Siren Moving Away From Observer Wavelengths Used in Ultrasound |
The waves will bunch up and the frequency will increase and the wavelength will decrease.
The waves will spread out and the frequency will decrease and the wavelength will increase. Shorter wavelengths are used as they diffract much less than longer wavelengths, therefore they spread out less and give a clearer image. |
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EM Waves
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They are progressive waves and carry energy, they can also be polarised. The following are all part of the EM spectrum:
Radio waves, Microwaves, Infrared, Visible Light, Ultraviolet Light, X-Rays and Gamma Rays. |
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Light Travels from an optically Denser material to a Less dense
Total Internal Reflection |
The glass to air boundary is an example. When light is shined at a glass to air boundary the angle of incidence starts to increase. This causes the angle of refraction to get closer and closer to 90 degrees. Eventually i reaches the critical angle = 90 degrees and the light is refracted along the boundary.
This is when the angle of incidence is larger than the critical angle and all the light is reflected back into the material. |
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Superposition
Coherent Constructive Interference Destructive Interference |
When two or more waves cross and the resultant displacement equals the vector sum of the individual displacements.
Two sources are coherent if they have the same wavelength and frequency and a fixed phase difference. It occurs when the path difference is a whole number of wavelengths. It occurs when the path difference is a odd number of half wavelengths. |
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Standing Waves
Oscillation of Standing waves Fundamental Frequency Second Harmonic |
They are produced when progressive waves are reflected at a boundary.
Each particle vibrates at right angles to the string, nodes are where the amplitude of the vibration is zero. It is when the standing wave is vibrating at the lowest possible resonant frequency, it has a loop with a node at each end. It is twice the fundamental frequency . |
