A student rubs a clean glass rod with a dry silk cloth.
After rubbing, the student finds that the glass rod has acquired a positive electrostatic charge.
Explain how the glass rod became positively charged.
47 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.