A Level Physics Session
|Gravitation||Waves and Interference||Magnetic Force||Photoelectric Effect|
Welcome to this session on photoelectric effect. The following are two videos on this topic.
ExercisesPlease try these questions.
- There are two metal plates A and B in a glass tube. The air in the tube has been mostly pumped out.
When a 470 nm light shines on A, a voltage is measured across AB. What is the colour of this light?
- Why does a voltage appear across AB? If we think of this as a cell, which plate is the positive pole?
- Find the frequency of the light. Find the energy of each of its photons.
- It takes at least 2.28 eV to remove an electron from metal A. What is the name of this energy?
- An electron absorbs the energy of one of the photons and jumps out of the metal plate. What is the range of possible energies of this electron?
- Why do the emitted electrons not all have the same energy?
- If A and B are connected by a piece of wire, a current flows. I want to connect a battery in the reverse direction to A and B to stop this current. What voltage must I use?
- What do you think the voltage in (ii) above might be? Why?
Past Exam QuestionsIn this video, I shall go through some questions from a past exam paper.
Thanks for attending this session.
5 May 2014