What is the kinetic energy of an electron in electronvolts with mass equal to double its real mass?

Explanation

`Delta m = m-m_0 = 2m_0 - m_0 = m_0`
Energy 'E' = m_0c^(2) = 9.1 xx10^(-31) xx 9 xx 10^(16)J`
` E` in ev = 9.1 XX 9 / 1.6 XX 10^(15) / 10^(-19) = 51.18 XX 10^(4) eV = 511KeV` .