What is the inertia of EM wave or field

Another useless link and a strong candidate for the title of King of Moronica

The constant of the speed of light demonstrates its energy is not kinetic. As all light waves would be of the same colour if their energy were kinetic.

Mitchell Raemsch

There is no kinetic energy in light or EM wave as the fields are mass-less. The question is about inertia.

Mathew Orman

Photons have momentum. Look it up.

John

s.

There's energy associated with photons, and - as Einstein pointed out

- energy can be equated to mass. Photons may not have rest mass, but if they were resting they wouldn't exist.

And photons have momentum and thus inertia. The question is ill-posed.

-- Bill Sloman, Nijmegen

That argument doesn't work for ball-bearings compared with bowling balls. Why should it work for photons?

-- Bill Sloman, Nijmegen

Yes, so they must also have inertia.

Mathew Orman

Then how much inertia a photon has?

Mathew Orman

It's the "Dopeler Effect". The ideas sound better the faster they come at you. :)

Why are we feeding the troll?

-- My liberal friends think I'm a conservative kook. My conservative friends think I'm a liberal kook. Why am I not happy that they have found common ground?

Tim Wescott, Communications, Control, Circuits & Software

They have momentum but zero mass, and only exist at one speed. I don't think it's meaningful to talk about their inertia.

John

No, but we can talk about the permitivity and permeability of free space, which are properties that determine the EM velocity in free space, and hence can conceptually be viewed as an "inertia" (if we stretch things).

s.

Inertia is perpetual motion. There is no absolute rest. It can be linear or circular.

Mitch Raemsch; the prize

I have had one of these on my window sill since i was a kid..

Mark

Photons at rest? How do you manage that?

OK, what is the inertia of, say, a 500 nm photon? And what are the engineering units of same?

John

But they spin backwards!

John

EM waves don't have linear inertia but they do have "rotational inertia" AKA angular momentum.

Launching in only negative three days!

Mark L. Fergerson

"Let's not get started on radiometer's".. (fanning the flames.)

There's all this theory about holes in the vanes... but no real data!

Perhaps someone could write an NSF grant?

George H.