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sheld
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Why phase difference of EM wave is changed 180 degrees reflected from denser medium?
I will be glad if u give me the actual reason [emoji4]
I will be glad if u give me the actual reason [emoji4]
The 'reason' can be explained in terms of a change of impedance and the requirement for continuity at the boundary. At the interface, there has to be continuity of E and H fields - as a wave crosses, if the ratio of E/H changes (different phase velocity) then there must be a reflected wave because all the energy can't pass through. One or other of the Electric or Magnetic fields in the reflected wave will be in anti phase so that there is no change in field across the boundary. Which one changes sign, depends on whether the impedance of the second is greater or less than the impedance of the first medium.sheld said:Why phase difference of EM wave is changed 180 degrees reflected from denser medium?
I will be glad if u give me the actual reason [emoji4]
The OP wants a reason / explanation, though. Why would you expect the reflection from a lower index of refraction boundary to be in phase?Leesa Johnson said:An electromagnetic wave undergoes a phase change of 180° upon reflection from a medium that has a higher index of refraction than the one in which the wave is traveling.
Phase difference refers to the difference in phase between two waves. It occurs because waves are constantly changing, and when two waves are added together, their individual phases can either add up or cancel out, resulting in a phase difference.
Phase difference is measured in degrees or radians. It can be calculated by comparing the starting points of two waves or by measuring the time it takes for the waves to complete one full cycle.
A phase difference of 180° occurs when two waves are completely out of phase, meaning they are in opposite directions. This can happen when two waves with the same amplitude and frequency are added together, but one is shifted by half a wavelength.
A phase difference of 180° results in a phenomenon called destructive interference. This means that the two waves cancel each other out and the resulting wave has a lower amplitude or even disappears completely.
Yes, a phase difference of 180° can be used in noise-cancelling technology, where two sound waves with opposite phases are produced to cancel each other out and reduce background noise. It is also used in antennas and radio transmissions to help improve signal quality.