(a)[2]
State what is meant by the term de Broglie wavelength.
(b(i))[2]
An electron is accelerated from rest in a vacuum through a potential difference of $850\,\text{V}$. Show that its final momentum is $1.6 \times 10^{-23}\,\text{N s}$.
(b(ii))[2]
Calculate the de Broglie wavelength for this electron.
(c)[5]
Describe an experiment that demonstrates the wave nature of electrons. You may include a diagram if you wish.