1. An electron moves at 30,000 ms-1. What is its de Broglie wavelength?
2. What is its frequency?
3. What is its kinetic energy, in eV?
From the top half of the fraction in the previous question:
4. Given that it is travelling out of an electron gun, what was the potential difference between the anode and the cathode?
2.56 mV – that's why we use eV!
5. An electron is accelerated by a potential difference of 150 V. What is its frequency?