Exploring the Momentum of Light and EM Radiation on Electrons

In summary: Radiation pressure is the pressure exerted on an object by radiation. It arises because the energy of the radiation is converted into heat, which then has to go somewhere. The pressure is highest near the source of the radiation, and decreases as the radiation moves away from the source.
  • #1
k9b4
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Is the momentum of EM radiation due to the EM radiation applying a force on the electrons?
 
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  • #3
Bandersnatch said:
You're probably thinking of something like this:
http://en.wikipedia.org/wiki/Compton_scattering
I don't think that's what I'm thinking of.

I mean:
Light is said to possesses momentum. That means it can push things around right? So I'm asking is the reason light can push stuff around because EM wave pushes electrons?
 
  • #4
k9b4 said:
I mean:
Light is said to possesses momentum. That means it can push things around right? So I'm asking is the reason light can push stuff around because EM wave pushes electrons?

Yes, that is the basic mechanism by which light (which is electromagnetic radiation) transfers energy and momentum to objects.

But do note the word "basic" - entire books can be and have been written on the interaction of light and matter.
 
  • #5
Nugatory said:
Yes, that is the basic mechanism by which light (which is electromagnetic radiation) transfers energy and momentum to objects.

But do note the word "basic" - entire books can be and have been written on the interaction of light and matter.
Thanks, basic mechanism is all I wanted.
 
  • #6
Nugatory said:
Yes, that is the basic mechanism by which light (which is electromagnetic radiation) transfers energy and momentum to objects.

But do note the word "basic" - entire books can be and have been written on the interaction of light and matter.
But hold on, how does EM radiation push objects forward (such as in solar sails)? Isn't the force in EM radiation oscillating perpendicular to the direction of travel?
 
  • #7
k9b4 said:
But hold on, how does EM radiation push objects forward (such as in solar sails)? Isn't the force in EM radiation oscillating perpendicular to the direction of travel?

An electromagnetic wave has both an electrical and a magnetic component. Both fields are perpendicular to the direction of travel. However, the force exerted by these fields is not in general parallel to the field direction. (google for "Lorentz force").
 
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FAQ: Exploring the Momentum of Light and EM Radiation on Electrons

What is the momentum of light and electromagnetic radiation?

The momentum of light and electromagnetic (EM) radiation is a measure of the amount of motion or energy carried by these particles. This momentum is described by the famous equation E=mc^2, where c represents the speed of light. This equation shows that light and EM radiation have both energy and momentum, just like any other object with mass.

How does light and EM radiation interact with electrons?

Light and EM radiation can interact with electrons in several ways, such as by transferring energy or momentum to the electrons. This interaction is the basis for many phenomena, including the photoelectric effect, where light can knock electrons out of a material, and the Compton effect, where photons collide with electrons and change their momentum.

How does the momentum of light and EM radiation affect the behavior of electrons?

The momentum of light and EM radiation can have a significant impact on the behavior of electrons. For example, high energy photons can cause electrons to move faster and farther, while lower energy photons may not have much effect. Additionally, the direction and speed of the photons can also influence the movement of electrons.

Can the momentum of light and EM radiation be measured?

Yes, the momentum of light and EM radiation can be measured using various techniques, such as with special instruments that can detect and measure the energy and direction of photons. Scientists can also use mathematical equations and models to calculate the momentum of light and EM radiation in different scenarios.

How does the momentum of light and EM radiation relate to the wave-particle duality of light?

The concept of wave-particle duality states that light and other particles can exhibit both wave-like and particle-like behaviors. The momentum of light and EM radiation is an essential aspect of this duality, as it shows that light can behave as a particle with mass and momentum, while also exhibiting wave-like properties, such as diffraction and interference.

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