According to Louis de Broglie, a French physicist, every moving material particle has a dual nature i.e., wave and particle nature. The two characters are co-related by de Broglie relation `lambda=(h)/(m upsilon(p)).` Here `lambda` represents wave nature while p or `m upsilon` accounts for the particle nature. Since h is constant , the two characters are inversely proportional to each other. This relationship or equation is valid mainly for microscopic particles such as electrons, protons, atoms, ions, molecules etc. It does not apply to semi-micro or micro particles.
If travelling at equal speeds, the longest wavelength of the following matter waves is for

Options

A. an electron
B. a proton
C. a neutron
D. an `alpha`-particle `(He^(2+))`.

Answer

A

Explanation

For electron wave, mass (m) is the least and wavelength (l) is the maximum `(lambda=(h)/(m upsilon))`