A student hangs a polythene rod from a thread so that the rod can turn freely.
The student rubs the hanging rod with a duster. The hanging rod becomes negatively charged.
The student then rubs some other objects and brings each one close to one end of the hanging rod.
The Table shows the results.
Table
| Object brought close to the hanging rod | What the hanging rod does |
|---|---|
| a second polythene rod rubbed with a duster | moves away from the object |
| an acetate rod rubbed with a duster | moves towards the object |
| the duster used to rub the hanging rod | moves towards the object |
Give the type of charge on the second polythene rod.
Give a reason for your answer.
Deduce the type of charge on the acetate rod.
Explain your answer using the Table.
Explain, in terms of electrons, how the acetate rod becomes charged when it is rubbed with the duster.
Predict what happens when two acetate rods, both rubbed with dusters, are brought close together.
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.