PHY 201
Your 'cq_1_26.1' 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 simple pendulum has length 2 meters. It is pulled back 10 cm from its equilibrium position and released. The tension in the string is 5 Newtons.
Sketch the system with the pendulum mass at the origin and the x axis horizontal.
answer/question/discussion:
Sketch a vector representing the direction of the pendulum string at this instant. As measured from a horizontal x axis, what is the direction of this
vector? (Hint: The y component of this vector is practically the same as the length; you are given distance of the pullback in the x direction. So you
know the x and y components of the vector.)
answer/question/discussion:
87.1 degrees counterclockwise from x axis
What is the direction of the tension force exerted on the mass?
answer/question/discussion:90-87.1 = 2.9 + 90 = 92.9 degrees
Depending on which way you pull the string back, you could get 92.9 deg or 87.1 deg for the direction of the string. However the tension will be in the same direction.
What therefore are the horizontal and vertical components of the tension?
answer/question/discussion:
5cos(92.9) = -.25
5sin(92.9) = 4.99
What therefore is the weight of the pendulum, and what it its mass?
answer/question/discussion:
I'm not sure how to find the weight/mass.
I know it has something to do with gravity pulling down on it and the y comp being 4.99 N
The system is not accelerating in the y direction, so the y component of the tension is equal and opposite to the weight. The weight is mass * accel of gravity. So you can find the mass.
What is its acceleration at this instant?
answer/question/discussion:
I would have to know the mass to find this
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25 min
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&#At least part of your solution does not agree with the solution and comments given at the link below. You should view the solution at that link and self-critique as indicated there.
Solution
This link also expands on these topics and alerts you to many of the common errors made by students in the first part of this course. &#