Showing Revision 1 created 07/23/2012 by Amara Bot.

1. Title:
   06-11 Pulley Quiz Solution
2. Description:

   All units in this course below:

   Unit 1: http://www.youtube.com/playlist?list=PLF79FCD2E20F4F9FC
   Unit 2: http://www.youtube.com/playlist?list=PL0E63503E8232BB23
   Unit 3: http://www.youtube.com/playlist?list=PL9BF147060D26ADF6
   Unit 4: http://www.youtube.com/playlist?list=PLDB3B73A8BCD831C3

   Join the class at http://www.udacity.com to gain access to interactive quizzes, homework, programming assignments and a helpful community.

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   Let's look at a triple pulley. We'll first see have a triple pulley work.
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   We would wrap around this top pulley.
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   Go down around the bottom, wrap once more around the top
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   and then connect somewhere in the middle here.
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   Now we can see that the tension is pulling upwards one, two, three times.
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   The force diagram for that is well, the weight points down
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   and we have three arrows upwards each representing that tension.
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    Since the weight is a 1000 N, these each balance 1/3 of that and so we get a force of 333 N.
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    Of course the consequence is that your going have to pull three times further
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    than you did in the single case.
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    You can do similar thinking to solve for the quadruple pulley.
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    Now you may already be seeing a very amazing pattern emerging from this data.
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    Before we explicitly point it out there, why don' we calculate
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    one more method for lifting this rock by 1 m, let's look at an incline plane.