A metal sphere stands on an insulating stand.
The sphere is given a negative charge.
Explain why the sphere stays charged.
A student connects the sphere to earth using a copper wire.
Describe the movement of electrons when the sphere is connected to earth.
Explain why a copper wire is used and not a plastic thread.
The sphere is now given a positive charge.
The student connects the sphere to earth again.
Describe how the movement of electrons is different from (b)(i).
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.