A crop sprayer gives the insecticide droplets a negative charge as they leave the nozzle.
The plants in the field are connected to earth through their stems and roots, so their leaves become positively charged as the droplets approach.
Explain why the charged droplets form a fine, even spray instead of joining together into large drops.
Uncharged droplets mainly land on the top surfaces of the leaves.
Explain why charged droplets also coat the undersides of the leaves.
Give two advantages of using charged droplets, for the farmer or for the environment.
A farmer says:
'Because the droplets are charged, I can spray on a windy day and none of the insecticide will be blown away.'
Explain why the farmer is wrong.
80 exam-style questions on Edexcel GCSE Physics 11.2 Uses, dangers and electric fields, covering 11.2.1 Uses of electrostatic charge, 11.2.2 Dangers of sparking, 11.2.3 Electric fields, and 11.2.4 Electric fields and static electricity. Each one has a worked solution and a mark scheme showing where the marks go.