Three dry insulating discs A, B and C are initially neutral. Each disc is made from a different insulating material.
A and B are rubbed together and separated. A is placed on an insulating support. B is then rubbed with C and separated. No charge leaks away during the procedure.
| Stage | Object measured | Charge / nC |
|---|---|---|
| after A and B are rubbed together | A | -8.0 |
| after B and C are rubbed together | B | +3.0 |
Explain the final charge on C, then predict whether A and C attract or repel, giving a reason.
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.