If the kinetic energies of an electron, an alpha particle and a proton is E₁, E₂ and E₃ respectively with same de Broglie wavelength, then what will be the relation between these energies?

 E₁=E₂=E₃ 

The relation between de Broglie wavelength and kinetic energy is given by 

\(\lambda \)=\(\frac{h}{2mK}\)

So, if \(\lambda \) is same for all the particles, their kinetic energies will also be same i.e. E₁=E₂=E₃.