Uses of static electricity
2 marks · EasyDescribe why paint droplets in electrostatic spraying repel each other as they leave the spray gun.
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They all have the same type of electric charge, so they repel each other due to electrostatic repulsion.
Also accept: Each paint drop gets the same charge and like charges repel.
Common mistakes: Saying gravity causes the droplets to spread.; Not mentioning the charge.
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Marking points
B1 · 1 mark · States the droplets all have the same charge.
B2 · 1 mark · Mentions that like charges repel (electrostatic repulsion).
Worked solution
Each droplet is given the same charge as it leaves the spray gun. Like charges repel each other, so the droplets spread out.