cq_1_161

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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?

answer/question/discussion: ->->->->->->->->->->->-> :

= [sqrt] 8^2 + 5^2

= [sqrt] 89

= + - 9.4 cm = 9.4 cm

T = 0.7 N * 9.4 cm

= 6.6 Newtons

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• What is the vector from the first point to the second?

answer/question/discussion: ->->->->->->->->->->->-> :

9.4 – 7.5 cm = 1.9 cm

1.9 cm * 0.7 Newtons = 1.33 Newtons

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• What is the magnitude of this vector?

answer/question/discussion: ->->->->->->->->->->->-> :

= [sqrt] 8^2 + 5^2

= + - [sqrt] 89

= 9.4 cm

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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: ->->->->->->->->->->->-> :

We get the unit position vector.

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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: ->->->->->->->->->->->-> :

Tension vector = 1 * 9.4 magnitude. = 9.4 Newtons

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• What are the x and y components of the new vector?

answer/question/discussion: ->->->->->->->->->->->-> :

T_x_ = T cos 0-

T_y_ = T sin 0-

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1 hour

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10/19 3 pm

You're on the right track, but you should submit a revision on this one.

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