Phy 201
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?
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#$&* I wasn’t completely sure how to do this problem…. but I set up the points (5, 9) and (10, 17) on a coordinate plane, and then formed the line into a right triangle. From there I used a^2 + b^2 = c^2 to determine the length of the line to be approximately 9.4 cm. So if the rubber band was stretched to this length, it would have T = 0 up to 7.5cm, and then the T would = .7N / cm from there on out. So (9.4cm – 7.5cm) * 0.7 N = 1.33 Joules.
• What is the vector from the first point to the second?
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#$&* I’m guessing what you want here is the length of the coordinate line? In that case, the vector was 9.4 cm.
• What is the magnitude of this vector?
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#$&* Or maybe the magnitude of the vector is 9.4cm. I’m not really sure. There is no Introductory Problem Set for Assignment 16 to go over this information….
Introductory problem set 5 was initial assigned in Asst 14, and that part of the assignment should provide sufficient information to do this problem. You're correct so far.
• What vector do you get when you divide this vector by its magnitude? (Specify the x and y components of the resulting vector).
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#$&* I read over Chapter 3 to get a more thorough understanding of vectors, and that left me more confused.
• 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?
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#$&* Well, I determined the Tension to be 1.33 Joules, so this new vector of 1/T = 0.752 (I don’t know what the units would be).
• What are the x and y components of the new vector?
answer/question/discussion: ->->->->->->->->->->->-> :
#$&* If the new vector is 1, I would guess the x & y components would maybe be approximately 0.71 and 0.71, since ‘sqrt(.71^2 + .71^2) = 1
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
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about 45 minutes...
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I definitely need an Intro Prob Set on vectors. I was completely lost on this Seed assignment....
I'm glad you're making use of the Introductory Problem Sets and apparently find them helpful.
You aren't doing badly on this question. Check the link, as instructed below:
&#Please compare your solutions with the expanded discussion at the link
Solution
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