Electrons with an energy of 0.842 eV are incident on a double slit in which the two slits are separated by 40.0 nm. What is the speed of these electrons?

A photographic film is coated with a silver bromide layer. When light falls on this film, silver bromide molecules dissociate and the film records the light there. A minimum of 0.6 eV is needed to dissociate a silver bromide molecule. Find the maximum wavelength of light that can be recorded by the film.

A single beam of electrons shines on a single slit of width 8.7nm. A diffraction pattern (of electrons!) is formed on a screen that is 3.9m away from the slit. The distance between the central bright spot and the first minimum is 5.7cm.What is the kinetic energy (keV, i.e. kilo electron-Volts) of the electrons?Make use of the small angle approximation.

A highly collimated (parallel) beam of electrons is shot through a single slit of width 17.5μm. The electrons are moving with a speed of 7.357.35km/s. When they hit the screen, located at distance 1.57m away, the distribution of hitting positions makes a pattern with a central peak and minima on either side. What is the width of the central peak (equivalently, distance between the minima on either side)?   The mass of an electron is 9.11×10​^−31​​ kg.