What must be the velocity of a beam of electrons if they are to display of de-Broglie wavelength of `100overset(@)A`?

What is the de Broglie wavelength

If photon and an electron have same de-Brogile wavelength then.

Calculate the de-Brogile wavelength of an electron.

An electron travels with a velocity of x ms^(-1). For a proton to have the same de-Broglie wavelength, the velocity will be approximately:

The kinetic energy of an electrons is equal to the energy of photons. Show that de-Broglie wavelength of this electrons is less than the wavelength associated with a photon.

Which of the following has the largest de Broglie wavelength (all have eual velocity)?