rest mass
1
7.4
- noun
- /rɛst mæs/
- Specialized
:
masa en reposo
- The rest mass of an object remains constant regardless of its speed.
That's given by the rest mass of the electron and positron E equals MC squared.
- That's given by the rest mass of the electron and positron E equals MC squared.
- So yes, light can push because it has momentum, it has no rest mass, but it does have relativistic mass.
- M will M is the rest mass, M is mass.
- This was the density of ordinary mass, ordinary rest mass.
Examples
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The equations predicted a previously unknown particle, one with the rest mass of an electron but possessing a positive charge.
Academic text (2005) -
In this equation, it's rest mass and rest energy.
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Any object that has a certain rest mass, we call the rest mass M.
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Where this M is known as the rest mass of this object.
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So suppose this guy has a rest mass M.
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Right, any frame of reference would measure the same rest mass for any given particle.
Blog text (22) -
When antimatter particles collide with their matter siblings, they convert all their rest mass into photon energy.
Academic text (2005) -
That's given by the rest mass of the electron and positron E equals MC squared.
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At relativistic speeds, relative mass increases to the point that, when accelerating to relative c, the nominal mass of the entity approaches infinity, which is why anything that has rest mass cannot reach the speed of light.
Blog text (22) -
In the Einsteinian, relativistic universe, by contrast, objects have an unchanging "rest mass" (the same as the "mass" in Newton's equations), to which you add more mass according to the object's speed.
Academic text (2004)
How Massive
Surface Forms
Morphology
rest + mass
The term is directly compositional: 'rest' (not moving) + 'mass' (amount of matter) yields 'mass when an object is at rest', so the core meaning is derivable from the constituents. Although the full technical nuance (intrinsic property independent of motion/gravity) is specialized, the basic sense is transparent and cross-linguistically paralleled, so a B1 learner who knows both words would grasp the main meaning.
Etymology
Rest mass comes from the idea of measuring mass when an object is at rest; imagine putting something on a scale when it is 'not moving' to see how heavy it really is. So, rest mass means the object's mass measured while it is still, and this value does not change when the object moves.