Example for Poynting's Theorem

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Poynting's Theorem relates to the conservation of energy in electromagnetic fields, and a practical example is the use of laser tweezers. Laser tweezers operate by trapping particles through light scattering, where momentum is transferred from the light to the particle. The discussion highlights the importance of the Poynting vector integral in understanding energy flow. Additionally, the conversation suggests that there are various resources available for further exploration of this topic. The inquiry emphasizes a desire for an engaging problem related to Poynting's Theorem.
shynee
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Hi,

Anyone knows a good example to aply Poynting's Theorem?

The one thas defines the conversation of energy in the electromagnetic field?

Regards Martin
 
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Laser tweezer?

I don't have a clue, how they work.

Which parts of the Equaction are involved?

The integral of the Poyntig Vektors, and which more?
 
Absorbed sunlight, heating a surface.
 
shynee said:
Laser tweezer?

I don't have a clue, how they work.

Which parts of the Equaction are involved?

The integral of the Poyntig Vektors, and which more?

A laser tweezer maintains a trapped object by light scattering. Momentum from the light is transferred to the trapped particle. Alternatively, the focused beam of light creates a potential well for the particle.

There's lots of material out there- my understanding was that you were looking for an interesting problem to solve. Is that wrong?
 

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