Help with this Pretend "ACT" Physics Question :)

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<p>Hi, I have tried getting help elseware, but no one seems to want to answer my extremely "fun" question. So, after a bit of thinking I thought my besties on College Confidential would help me!</p>

<p>Warning: I know this is not a true ACT question, and that's why it says Pretend :)</p>

<p>Also, good luck to everyone tonight; I hope you get the score you need!</p>

<p>Without any further distractions here's the questions.</p>

<p>A student tries to time the period of a pendulum using the sweep-second hand of a wall clock. She releases the pendulum from an initial angle of 10 degrees, but by the time she counts 100 cycles, the angle has decayed to only 5 degrees. </p>

<ol>
<li><p>Is her timing of the average period of 100 cycles reliable?...because...?</p></li>
<li><p>If her timing of 100 cycles is 146 seconds, what period should she report?</p></li>
<li><p>If she timed only 50 cycles and got 73 seconds, what period should she report?</p></li>
</ol>

<p>Thanks SO much in advance! :)</p>

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<p>Also, can someone please explain the “Power Law” to me? (:</p>

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<p>No, we wont do your Physics homework for you.</p>

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<p>This is part of a 14 page Physics formal lab report. There are many more questions that I did by myself. I am just stuck on these two things.</p>

<p>No need to be rude. :(</p>

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<p>All the student needs is the length of the pendulum to calculate the period. Say that the student should find a ruler and calculator and find the period using the equation for the period.</p>

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<p>The timing is still accurate because the angle of the swing will not affect the length of time for the period. The only factors for the period’s time is length of the string and gravity. 2 and 3 should both still be 1.46 seconds.</p>

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<p>Thanks jessez2007! :)</p>

<p>That’s what confused me; I thought the angle had a very small influence on the period. :)</p>

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<p>Ok.To question number 1. The period of a pendulum can be represented by P=(pi) (L/g)^1/2 the L represents Length of the string. G is gravity (which is always constant) the “^1/2” means square root of the “L/g”. as you can see, out of the three numbers used, none of them deal with the angle. this is because of the kinematics taking place. when it travels from the angle of 10 degrees, it is able to reach a higher velocity then when it is falling from 5 degrees. The differences in velocity, as well as the differences in distance travelled (due to the differences in angles) equal out. With this, the period can stay constant despite the change in angles. in reference to number 2 and 3, the answer to both should be 1.46 seconds as the period is cycles per second.</p>

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<p>Read your physics book. It has formulas in it. Use the formulas…</p>

<p>That’s what most of us do…</p>

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<p>Damn what a genius, college confidential as “do your hw for you”
I’ll upload my next physics work sheets see if anyone helps xD</p>

<p>Lol jk I do my own stunts.</p>

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<p>I took the lab class with out the lecture so I didn’t have a book :(</p>