Examples of medium in the following topics:
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- A laser consists of a gain medium, a mechanism to supply energy to it, and something to provide optical feedback.
- When a gain medium is placed in an optical cavity, a laser can then produce a coherent beam of photons.
- The gain medium is where the optical amplification process occurs.
- The most common type of laser uses feedback from an optical cavity--a pair of highly reflective mirrors on either end of the gain medium.
- A single photon can bounce back and forth between the mirrors many times, passing through the gain medium and being amplified each time.
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- Refraction is a surface phenomenon that occurs as the change in direction of a wave due to a change in its medium.
- Refraction is the change in direction of a wave due to a change in its medium.
- Due to change of medium, the phase velocity of the wave is changed but its frequency remains constant (most commonly observed when a wave passes from one medium to another at any angle other than 90° or 0°).
- Refraction of light is the most commonly observed phenomenon, but any type of wave can refract when it interacts with a medium (e.g., when sound waves pass from one medium into another or when water waves move into water of a different depth).
- In optics, refraction is a phenomenon that often occurs when waves travel from a medium with a given refractive index to a medium with another at an oblique angle.
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- The Doppler Effect is the change in a wave's perceived frequency that results from the source's motion, the observer, and the medium.
- Finally, if the medium through which the waves propagate moves, the Doppler effect will be noticed even for a stationary observer.
- Quantitatively, the Doppler effect can be characterized by relating the frequency perceived (f) to the velocity of waves in the medium (c), the velocity of the receiver relative to the medium (vr), the velocity of the source relative to the medium (vs), and the actual emitted frequency (f0):
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- Apparatus: A hologram can be made by shining part of the light beam directly onto the recording medium, and the other part onto the object in such a way that some of the scattered light falls onto the recording medium.
- Some of the light scattered (reflected) from the scene then falls onto the recording medium.
- Several different materials can be used as the recording medium.
- Process: When the two laser beams reach the recording medium, their light waves intersect and interfere with each other.
- It is this interference pattern that is imprinted on the recording medium .
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- When the medium changes, a wave often experiences partial transmission and partial refection at the interface.
- When the medium through which a wave travels suddenly changes, the wave often experiences partial transmission and partial refection at the interface.
- Reflection is a wave phenomenon that changes the direction of a wavefront at an interface between two different media so that the wavefront returns into the medium from which it originated.
- k1 and k2 are determined by the speed of the wave in each medium.
- A wave experiences partial transmittance and partial reflectance when the medium through which it travels suddenly changes.
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- This means that the movement of the medium is in the same direction as the motion of the wave.
- The difference is that each particle which makes up the medium through which a longitudinal wave propagates oscillates along the axis of propagation.
- Sound waves are created by the compression of a medium, usually air.
- Matter in the medium is periodically displaced by a sound wave, and thus oscillates.
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- For a fluid at rest, the conditions for static equilibrium must be met at any point within the fluid medium.
- Similarly, the sum of the forces and torques of an object at rest within a static fluid medium must also be zero.
- In considering a stationary object within a liquid medium at rest, the forces acting at any point in time and at any point in space within the medium must be analyzed.
- In analyzing such a simple system, consider a rectangular region within the fluid medium with density ρL (same density as the fluid medium), width w, length l, and height h, as shown in .
- Next, the forces acting on this region within the medium are taken into account.
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- Wave motion transfers energy from one point to another, often with no permanent displacement of the particles of the medium—that is, with little or no associated mass transport.
- Mechanical waves propagate through a medium, and the substance of this medium is deformed.
- The second main type of wave, electromagnetic waves, do not require a medium (although they may still propagate through a medium).
- This waveform gives the displacement position ("y") of a particle in a medium from its equilibrium as a function of both position "x" and time "t".
- To find the velocity of a particle in the medium at x and t, we take the temporal derivative of the waveform to get $\frac{\partial y(x,t)}{\partial t} = -A \omega cos(kx - \omega t + \phi)$.
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- During a phase transition, certain properties of the medium change, often discontinuously, as a result of some external condition.
- During a phase transition of a given medium certain properties of the medium change, often discontinuously, as a result of some external condition, such as temperature or pressure.
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- The speed of sound is is the distance traveled in a unit of time by a sound wave through an elastic medium, and is usually given as 344 m/s.
- The speed of sound is is the distance traveled in a unit of time by a sound wave through an elastic medium.
- This medium can be a solid, liquid, gas or even plasma.
- The Mach number is given by the following, dimensionless equation:$M=\frac va$M - Mach numberv - Velocity of object a - Speed of sound in medium.