cq_1_261

Phy 231

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

The x-component is 0.1, the hypotenuse is 2, so the y-component is 1.99. The angle the pendulum makes with the x-axis is 2.9 degrees. Add 2.9 to 90 degrees, and the direction is 92.9 degrees.

• What is the direction of the tension force exerted on the mass?

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

The direction of the tension force on the mass is 92.9 degrees.

• What therefore are the horizontal and vertical components of the tension?

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

The components would be (5cos92.9, 5sin92.9)

• What therefore is the weight of the pendulum, and what it its mass?

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The weight of the pendulum would be its y-component, which is 5sin92.9, which is 4.99.

• What is its acceleration at this instant?

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

I'm not sure what the acceleration would be. My guess is 9.8 m/s^2 because of gravity? Or 9.8sin92.9.

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20 min

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Everything looks good up to the last question or two. Check the link, whichyou will understand.

&#Please compare your solutions with the expanded discussion at the link

Solution

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