If E1 , E2 and E3 are the respective kinetic energies of an electron, an alpha particle and a proton each having the same de-Broglie wavelength then
(a) E1 > E3 > E2
(b) E2 > E3 > E1
(c) E1 > E2 > E3
(d) E1 = E2 = E3
Correct option (a) E1 > E3 > E2
Explanation:
For alpha mass is more hence its velocity is less leading to lowest k.E. In the same way mass of electron is less, hence its velocity is more leading to max k.E. Thus
EElectron >EProton>Ealpha