How Does Absorbing an Electric Field Affect the Magnetic Field Across a Surface?

E-field).In summary, using Maxwell's equations, we can determine that the magnetic field on the other side of the surface will be constant with respect to time and irrotational. This is based on the assumption that there is nothing else affecting the magnetic field on the other side of the surface.
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Homework Statement


An electromagnetic wave is incident on a surface which absorbs all the electric field. Use Maxwell’s equations to determine the magnetic field on the other side of the surface.

Homework Equations



The Attempt at a Solution


My initial thought was that ##B=0## as a varying B field would produce an E field. But then I thought we could still have a constant E field that has no oscillations. Is this even possible (it doesn't seem likely to me).

Many thanks
 
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With the assumption that nothing "extraordinary" is happening on the other side of the surface (for example we could have another EM wave there or a static E-Field from a charge distribution), all you can deduce from Maxwell's equations is that:

-the magnetic field will be constant with respect to time . This follows from Faraday's law, you are right that the B field isn't necessarily zero but just constant wrt time(no time varying)

-the magnetic field will be curl-free (irrotational, or equivalently its curl will be zero) . This follows from Maxwell's-Ampere law, since we know that the E-field is zero on the other side
 

What is the absorption of electromagnetic (EM) waves?

The absorption of EM waves refers to the process by which electromagnetic energy is transferred from an incident wave to a material, causing the material to gain energy and increase in temperature. This is different from reflection, where the energy is bounced off the material, and transmission, where the energy passes through the material.

What factors affect the absorption of EM waves?

The absorption of EM waves is affected by the properties of the material, such as its composition, density, and thickness. It is also influenced by the frequency and intensity of the incident wave, as well as the angle at which it strikes the material.

How is the absorption of EM waves measured?

The absorption of EM waves is measured using a device called a spectrophotometer, which measures the amount of light absorbed by a material at different wavelengths. This information is then used to determine the material's absorption spectrum, which can help identify its composition and properties.

What are some practical applications of the absorption of EM waves?

The absorption of EM waves has many practical applications, including in medical imaging (such as X-rays and MRI), communication technologies (such as satellite and cell phone signals), and energy production (such as solar panels). It is also used in materials testing, monitoring air pollution, and studying the composition of distant objects in space.

How does absorption of EM waves relate to the color of objects?

The color of an object is determined by the wavelengths of light that it reflects and absorbs. Objects that appear a certain color absorb all other wavelengths of light except for those that make up that color. For example, a red apple appears red because it absorbs all wavelengths except for red, which it reflects. The absorption of EM waves is what allows us to see different colors in the world around us.

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