
#1
Mar3011, 05:03 PM

P: 2,568

1. The problem statement, all variables and given/known data
Uploaded with ImageShack.us The problem is EXACTLY the same. But one thing concerns me. The answer key said the force is [tex]27\mu N \hat{i}[/tex] From Walter Lewin's method, I got [tex]+27\mu N \hat{i}[/tex]. Help? 3. The attempt at a solution 



#2
Mar3111, 11:47 AM

P: 2,568

Is no one answering because no one is bothered to watch the video lol?




#3
Apr511, 07:05 PM

P: 2,568

Please...




#4
Apr511, 08:03 PM

P: 1,781

Question about this problem and Walter Lewin's video
Flip the paper over. Then your ihat will point the same way his does.




#5
Apr511, 10:35 PM

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PF Gold
P: 7,379

@fp: He means left to right, not top to bottom. LOL 



#6
Apr511, 10:48 PM

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Seriously, Mr. Lewin clearly states that the force is toward the left.
Therefore, it's in the [tex]\hat{i}[/tex] direction. 



#7
Apr611, 02:32 PM

P: 2,568





#8
Apr611, 05:21 PM

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PF Gold
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Use thinner paper, write darker and/or use a light table.




#9
Apr611, 05:36 PM

P: 2,568

...
but what if I want to do it mathematically? 



#10
Apr611, 07:37 PM

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PF Gold
P: 7,379





#11
Apr611, 11:24 PM

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AM 


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