A student holds a copper rod in her hand and rubs it with a cloth.
The copper rod does not become charged.
The student then rubs a polythene rod with the same cloth.
The polythene rod becomes negatively charged.
Explain these observations.
Describe how the student could change the experiment so that the copper rod becomes charged, and how the charged copper rod could then be discharged.
Your answer should refer to the movement of electrons.
91 exam-style questions on Edexcel GCSE Physics 11.1 Charging by friction, covering 11.1.1 Charging insulators by friction, 11.1.2 Forces between charges, 11.1.3 Electrostatic phenomena, and 11.1.4 Earthing and removing charge. Each one has a worked solution and a mark scheme showing where the marks go.