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Phy 121
Your 'cq_1_16.1' report has been received. Scroll down through the document to see any comments I might have inserted, and my final comment at the end.
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A rubber band has no tension until it reaches a length of 7.5 cm. Beyond that length its tension increases by .7 Newtons for every additional centimeter of length.
What will be its tension if its endpoints are at the points (5 cm, 9 cm) and (10 cm, 17 cm) as measured on an x-y coordinate system?
answer/question/discussion: ->->->->->->->->->->->-> :
The tension will be approximately 1.4N because the length of the line is 9.43cm, as found by the Pythagorean theorem (5^2+8^2=89 and sqrt(89)=1.93).
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What is the vector from the first point to the second?
answer/question/discussion: ->->->->->->->->->->->-> :
The vector from the first point is 9.43cm.
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That is the magnitude of the vector.
You also need to specify its direction, either by giving its components or its angle with the positive x axis.
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What is the magnitude of this vector?
answer/question/discussion: ->->->->->->->->->->->-> :
The magnitude of this vector is 9.43cm.
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What vector do you get when you divide this vector by its magnitude? (Specify the x and y components of the resulting vector).
answer/question/discussion: ->->->->->->->->->->->-> :
The vector divided by its magnitude is as follows:
9.43cm/9.43cm=1cm.
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The new vector should have magnitude 1. When you divide a vector by its magnitude the result is a vector with magnitude 1. We call a vector of magnitude 1 a unit vector. What vector do you get when you multiply this new vector (i.e., the unit vector) by the tension?
answer/question/discussion: ->->->->->->->->->->->-> :
When you multiply the unit vector by 1.4N, you get 1.4N because 1*1.4N = 1.4N.
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What are the x and y components of the new vector?
answer/question/discussion: ->->->->->->->->->->->-> :
The component of this vector is .9 and the y component is 1.2.
?????I really dont understand how you find this?????
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It is assumed that you have done the Introductory Problem Assignment from Assignment 14. If not, you should do that then fill in the missing details.
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This new vector is called the tension vector. It is a force vector which represents the tension. A force vector can be specified by its components, or equivalently by its magnitude and direction.
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40 minutes
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I don't really understand vectors.
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I expect that you'll understand vectors fine from Introductory Problem Set 5, but if not specific questions are welcome.
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