NOTE 1 When the speed of the particle is negligible compared to the speed of light, the difference between mass and rest mass is also negligible.
NOTE 2 The rest mass of particle X is denoted m(X) MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHX garuavP1wzZbItLDhis9wBH5garmWu51MyVXgarqqtubsr4rNCHbGe aGqk0di9Wr=fpeei0di9v8qiW7rqqrVepeea0xe9LqFf0xc9q8qqaq Fn0lXdHiVcFbIOFHK8Feea0dXdar=Jb9hs0dXdHuk9fr=xfr=xfrpe WZqaaeaaciWacmGadaGadeaabaGaaqaaaOqaaKqzGeGaamyBaiaacI cajugabiaabIfajugibiaabMcaaaa@3D7F@ or mX; for example me denotes the mass of electron.
NOTE 1 Lorsque la vitesse de la particule est négligeable par rapport à la vitesse de la lumière, la différence entre masse et masse au repos est aussi négligeable.
NOTE 2 La masse au repos de la particule X est notée m(X) MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHX garuavP1wzZbItLDhis9wBH5garmWu51MyVXgarqqtubsr4rNCHbGe aGqk0di9Wr=fpeei0di9v8qiW7rqqrVepeea0xe9LqFf0xc9q8qqaq Fn0lXdHiVcFbIOFHK8Feea0dXdar=Jb9hs0dXdHuk9fr=xfr=xfrpe WZqaaeaaciWacmGadaGadeaabaGaaqaaaOqaaKqzGeGaamyBaiaacI cajugabiaabIfajugibiaabMcaaaa@3D7F@ ou mX; par exemple me est la masse de l’électron.