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Why did people's hair stand on end when a person has touched the sphere of Van de Graaff generator?

Why did people's hair stand on end when a person has touched the sphere of Van de Graaff generator? Correct Answer The positively charged (+) hair was repulsed by the positive charged (+) person and each other.

CONCEPT:

  • Van de Graaff Generators: A Van de Graaff generator is an electrostatic generator that uses a moving rubber belt to accumulate electric charge on a hollow metal globe on the top of an insulated column, creating very high electric potentials. It produces very high voltage direct current (DC) electricity at low current levels.

 

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EXPLANATION:

  • Inside the Van de Graaff generator, there is a rubber band and rollers. As they are electrically insulated, when the motor turns they rub together and electrons are 'knocked' off causing a positive charge.
  • If you are also touching the globe (metal housing), you will slowly become positively charged including each of your hairs. As like charges repel, and hair is very light, they will try and get as far away from each other as possible, causing them to stand up.


So option 1 is correct.

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