rest mass

All matter, such as any object, has some rest mass.

That figure is almost twice the actual rest mass in the neighborhood.

A body in space has a rest mass which determines its gravitational field.

This tensor gives the rest mass for the entire system.

They're elementary particles, with no charge, and a tiny rest mass.

Clearly it must have a rest mass of zero, like a neutrino.

Because the wave is always moving and never actually at rest, it does not have a rest mass.

Objects without a rest mass, such as photons, also carry momentum.

"You can't get more energy out of matter than the rest mass energy, I know that.

Initially the electron at rest has just its rest mass energy.

It destroys the old idea that you cannot create more energy at a point than the rest mass of the matter residing there.

In fact, since photons have zero rest mass, all their energy is kinetic.

No "rest mass", but then photons are always moving.

But if the rest mass is zero it does not matter how many times you multiply it.

It can be converted to a useful equivalent form by making the replacement where m is the rest mass of the test body.

This is true in special relativity theory, even though individually photons have no rest mass.

Matter- Generally considered to be a substance (often a particle) that has rest mass and (usually) also volume.

A photon has no rest mass, but it has momentum.

Any object that has a rest mass of zero can never be at rest."

So, in effect, we lump that kinetic energy (if it is such) into the rest mass of the electron.

The smallest particle with non-zero rest mass is still the electron.

A hypothetical particle with imaginary rest mass would always travel faster than the speed of light.

The rest mass is only proportional to the total energy in the rest frame of the object.

"Well, what about particles that have what we call a resting mass of zero?"

This is a very small effect, however, since most of the energy in the object is in its rest mass.