AP Physics B Work Question

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1

<p>Somebody answer this quesiton please..</p>

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[quote]
a scraper is drawn over a tooth 20 times, each time moving a distance of 0.75 cm. The scraper is held against the tooth with a normal force of 5.00 N assuming a coeffiecent of friction of 0.90 between the scaper and the tooth, determine the work done to clean the tooth

[/quote]
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<p>ok so shouldnt the answer be 0 or is it just me? (Because it comes back to start positon)</p>

2

<p>W = 5<em>0.9</em>0.0075</p>

<p>NET work is 0, not the work done to clean the teeth.</p>

3

<p>Thanks man, i almost thought tha tnobody was going to answer...hah ai have another question that i m going to post on another thread if u know the answer plz share..</p>