rest mass


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rest mass

n.
The physical mass of a body when it is regarded as being at rest.
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References in periodicals archive ?
In addition to the above, a conclusion was drawn that the fractional charge of a particle could be attributed to the strong interaction between two or three quarks, whereas the zero charge and rest mass for neutrinos was brought about by the weak interaction in the transformation processes of fermions.
And in the case of the meson [[B.sub.c] = b[bar.c]], the rest mass equation is as follows.
To find the rest mass of the body, taking into account the fields we should write the ratio M = E / [c.sup.2] with V = 0.
(55) "The mass that a particle has when at rest is sometimes called its rest mass." Ohanian, Physics, vol.
l = h / mc = 10 -13 cm should have rest mass 275 times larger than that of electron mass.
property electron rest mass m 9.10938356(11) x [10.sup.-31] kg energy E = [mc.sup.2] 0.5109989461(31) MeV angular frequency 7.76344071 x [10.sup.20] Hz [omega] = E/[??] oscillation period 1.28808867 x [10.sup.-21] s [tau] = 1/[omega] wavelength 3.8615926764(18) x [10.sup.-13] m [lambda] = c/[omega] property proton rest mass m 1.672621898(21) x [10.sup.-27] kg energy E = [mc.sup.2] 938.2720813(58) MeV angular frequency 1.42548624 x [10.sup.24] Hz [omega] = E/[??] oscillation period 7.01515 x [10.sup.-25] s [tau] = 1/[omega] wavelength 2.1030891 x [10.sup.-16] m [lambda] = c/[omega]
According to Ue-Li Pen and Abraham Loeb (Harvard-Smithsonian Center for Astrophysics) and Neil Turok (Cambridge University), in certain circumstances a neutron star - a 20-kilometer-wide ball of pure nuclear matter - could spontaneously convert its entire rest mass into 1054 ergs of radiant energy in 11/41000 second.
"If you had enough rest mass to accelerate the particles to meet the Gott condition, you would close the universe," Farhi says.
This circumstance allows us to calculate the big G from the proton rest mass:
Here r is the comoving radius-vector, [DELTA] = [[delta].sup.[alpha][beta]][[partial derivative].sup.2]/([partial derivative][x.sup.[alpha]][partial derivative][x.sup.[beta]]) stands for the Laplace operator, G is the gravitational constant, and p represents the rest mass density in the comoving coordinates [x.sup.1] [equivalent] x, [x.sup.2] [equivalent] y, and [x.sup.3] [equivalent] z.
Fourth, additional laboratory indications that ordinary neutrinos have a bit of rest mass. Fifth, more sophisticated models of how galaxies will form with various combinations of the parameters, only a few of which combinations make what we see.