In the Davisson-Germer experiment,the nickel crystal acts as a .........

Statement $1$: The Davisson-Germer experiment established the wave nature of electrons. Statement $2$: If electrons possess wave nature,they can undergo interference and diffraction.

This question has Statement-$1$ and Statement-$2$. Of the four choices given after the Statements,choose the one that best describes the two Statements.
Statement-$1$: Davisson-Germer experiment established the wave nature of electrons.
Statement-$2$: If electrons have wave nature,they can interfere and show diffraction.

The Davisson-Germer experiment that first demonstrated the wave nature of matter used electrons accelerated to $54 \ V$. Determine the wavelength of the electrons in the Davisson-Germer experiment in $\mathring{A}$.

According to Bohr's theory,the electron in orbits has definite energy values. Then,according to the uncertainty principle,the lifetime of an excited state will be:

In the Davisson-Germer experiment,for which value of accelerating voltage was the intensity of the electron beam found to be maximum (in $V$)?