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course phy201
9/10 2:05 am
Class followup:`q001. Explain how you obtained the best data possible for the experiment with the domino and the pendulum.
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Procedure: Begin by marking a specific point on the pendulum line to ensure the same length every trial. Then, begin by putting the domino and pendulum at the 100 cm mark, and drop them. Repeat for two or three trials to get a conclusive result. Once that is done, reduce the height by 10 cm. Repeat as needed until the result changes to where the domino hits the ground first.
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What were the maximum height at which the domino hit the floor first, and the minimum height at which the pendulum hit the wall first?
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50 cm and 80 cm
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What was the frequency of your pendulum?
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¼ oscillation/0.35 seconds, or 0.74 oscillations per second
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How much time elapsed from release until the pendulum hit the wall?
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0.35 seconds
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Calculate the acceleration based on this time interval and the maximum height at which the domino hit the floor first. Explain the details of your reasoning.
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80 cm. Average velocity of domino = 80 cm/0.35 seconds. Average velocity of domino = 228.5 cm/s. Final velocity = average velocity + (average velocity - initial velocity) = 228.5 + (228.5 - 0) = 457. Change in velocity = final velocity - initial velocity = 457 m/s - 0 m/s = 457 m/s. Average acceleration = change in velocity / time elapsed = 457 m/s / o.35 s = 914 cm/s^2
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Calculate the acceleration based on this time interval and the minimum height at which the pendulum hit the wall first.
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50 cm. Average velocity of domino = 50 cm/0.35 seconds. Average velocity of domino = 142.8 cm/s. Final velocity = 285.6 cm/s. Change in velocity = 285.6 cm/s. Average acceleration = 816 cm/s^2.
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`q002. How far apart were the two most widely separated balancing points for the unloaded steel ramp as it balanced on a domino?
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4 mm
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How far from the balancing point of the unloaded steel ramp was the balancing point when you had the ramp loaded with a domino near one end?
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28.6 cm
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How far was it between the two most widely separated positions of the domino at which the system remained balanced?
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3.5 cm
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Based on your results, which do you think weighed more when the loaded ramp was balanced, the part of the ramp on the 'longer' side, or the part of the ramp plus the domino on the other?
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The side with the dominoe. More movement could be attained without disrupting balance, indicating a greater difference.
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`q003. A ball rolls 58 cm down a ramp, starting from rest, and ends up moving at 30 cm / second. Assuming uniform acceleration, how long did it take to roll down the ramp, and what was its acceleration?
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Change in distance: 58 cm. Final velocity: 30 cm/s. Initial velocity: 0 m/s. Average velocity: 15 m/s. Change in time: 58 cm / 30 cm/s = 1.32 seconds. Change in velocity = 30 cm/s. Average acceleration = 30/1.32 = 23.08 cm/s^2. Time down ramp: 1.32 seconds. Average acceleration: 23.08 m/s^2
&#Very good work. Let me know if you have questions. &#