Forces between charged and uncharged objects
2 marks · NormalExplain why a girl’s hair stands on end after touching a Van de Graaff generator.
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Each strand of hair gains the same type of charge from the generator, so the hairs repel one another and stand apart.
Also accept: Repulsion between like-charged hair makes hair stand up
Common mistakes: Attraction between hairs
Show mark scheme and worked solution
Marking points
B1 · 1 mark · States that all hairs acquire the same type of charge
B2 · 1 mark · Explains that like charges repel, so hairs stand apart
Worked solution
The Van de Graaff generator gives each hair the same charge. Like charges repel, so the hairs push each other apart and stand on end.