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3 years ago

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A charged comb often attracts small bits of dry paper that then fly away when they touch the comb. Explain why that occurs.

1 answer:

MAVERICK [17]3 years ago

7 0

Explanation:

Since the comb has a net charge, it attracts the paper, which has a net charge equal to zero. When the paper touches the comb, an electrical interaction is established between the charge of the comb and the neutral paper, because of this, the paper now has a net charge with the same sign of the comb and they repel.

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Answer:

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As per the question:

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For z = 2.0, erf(z) = 0.998

For z = 2.2, erf(z) = 0.995

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$\frac{364.4}{\sqrt{t}} = 2.12$

$t = (\frac{364.4}{2.12})^{2}$ = 26700 s

t = $\frac{26700}{3600} = 7.42\ h$

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