Feppmaandu

Feppmaandu as wàll-wàllaanu xarefulwoon bi la. Di wenn ci wàll-wàllaan yi dàtt saalu xarefulwoon bi. Ni ko turam di junjee, feppmaandu dafa maandu moo tax amul yanu mbëj (du bu baax(+) mbaa bu bon(-)). Feppmaandu yeek feppsaal yi su ñu leen boolee ñooy nekk saalu xarefulwon bi. Ngir ab xarefulwoon, dañuy bind Z limu feppsaal yi, A di limu feppsaal + feppmaandu. Kon limu feppmaandu yi dafay doon N =A-Z.

Lefu feppmaandu mi ngi toll ci 939,56533 MmV. Ki ko wuññi mooy jëmmaan bu waa-angalteer ba James Chadwick ci 1932.