A student suspends a lightweight, statically charged polystyrene sphere from a thin nylon thread. They then suspend a second identical charged sphere from another thread nearby.
Explain how the student can show that the two spheres have the same type of electric charge.
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.