In a laboratory test, an insulating strip and a cloth are initially neutral. They are rubbed together. After rubbing, the strip has a charge of +4 nC.
Explain what this tells you about the charge on the cloth and the transfer 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.