Reflection
What is Reflection?
- A change in direction a wave experiences when it bounces off and/or passes through a barrier between two or more kinds of medium.
- The incoming wave or the original wave is called the incident wave. The angle the incoming wave bounces off of to form the reflective wave is called the angle of incidence.
- The wave that bounces back is known as the reflective wave
Law of Reflection
Fixed-end Reflection and Free-end Reflection
Fixed-end Reflecton
- Pulses reflected from a fix-end are inverted. Reflection forms a rigid obstacle when its pulse is inverted.
- A wave approaches a fixed-end from a medium bounces back inverted, or upside down from its original position.
- Fixed-end reflection always have the same wavelength and frequency. However, the amplitude can change, if it has a boundary or not. If it does have a boundary, then it goes into one direction, contacts the boundary, amplitude turns negative and then the wave returns to its staring position. If it doesn't, then the wave would go on it the exact same direction and amplitude
Free-end Reflecton
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Four Scenarios Overview
- Fixed End -> Waves go into one direction, stops, changes amplitude, and returns
- Free End -> Waves go into the opposite end, the boundary jumps up at higher frequency, and returns to the beginning in its original frequency
- Thinner to thicker -> The wave starts out fast and when it changes it medium, it continues in a slower frequency, but it also changes amplitude and reverses at the frequency of the difference at the y-axis
- Thicker to thinner -> The wave is at a constant amplitude throughout, but when it changes it medium, it gains frequency, and the different of the frequency is returned in the opposite direction
Example (analyzing)
- Wave travels in one direction
- Lands at its boundary
- Amplitude rises, and lowers after
- Returns in opposite direction at same amplitude
- Thus, it's a free end reflection
Applications of Reflection