An electrostatic paint sprayer is used to paint metal bicycle frames efficiently. The sprayer charges paint droplets as they pass through the nozzle.
State how the structure of an electrical insulator differs from the structure of a conductor.
The handle of the paint sprayer is made of plastic, which is an electrical insulator. Suggest why the handle is made from an insulator.
Explain, in terms of the particles involved, how the paint droplets become negatively charged and the nozzle becomes positively charged.
The sprayer transfers a charge of 7.5×10−3 C7.5 \times 10^{-3}\text{ C}7.5×10−3 C to the bicycle frame in a time of 5.0×10−4 s5.0 \times 10^{-4}\text{ s}5.0×10−4 s.
Calculate the average current of the charged paint droplets during this time.
145 exam-style questions on CIE IGCSE Physics 4.2.1a Positive and negative charge. Each one has a worked solution and a mark scheme showing where the marks go.