Does light have mass?

Question

I was told that anything that moves must have mass but what about light?

Answer 1

Supposedly, light (E) has as much mass (m) as it's amount divided by the square root of light speed (c2)!.. Isn't that that so? :S

That's what Einstein said one hundred years ago! E/c2=m,

or in his words E=mc2 :)

Answer 2

No. Sound like yiou misunderstood something.

Light is energy, and in that state it has no mass.

Answer 3

You were told that anything moves must have mass. Were not you told what should be the speed of mass?

Anything moving (whether light or not) at speed of light loses all its mass. It has no mass at all.

Answer 4

yes, infinite mass in fact.

mass in physics is not the same as mass in chemistry. mass in physics is the resistance to change it's state (state as in, velocity, for example). Have you ever stopped a beam of light? (stopped, not reflected or refracted). it's impossible, because it has infinite mass.

Answer 5

Yes, Light has Mass, Because light has energy, and energy has mass.

And if someone argues, (NO IN ORDER FOR IT TO TRAVEL THAT FAST IT CANT HAVE MASS) is complete BS, because they dont account for the electrons and photons. Because atoms have mass, therefore, if light has photons and atoms etc. It has mass.

Answer 6

No, light doesn't have mass.  The carrier particle of light is the photon, which is a boson.  Particles with mass are fermions.  Fermions obey the pauli exclusion principle and exhibit gravity, which bosons (force carrier particles) don't do.  Therefore, photons have no mass.  However, mass and energy are interchangeable, and since they have energy, their energy can be expressed in terms of mass, and converted to mass.  But since they don't exhibit the same behaviors as matter, they don't actually have mass.

Answer 7

Yes, as Einstein discovered, Light is both a Wave and Matter at the same time. And, since mass is one of the basic properties of 'matter', it can be deduced that Light does have mass.