Report your counts for the five trials with the toy car going in the first direction in the first line below, separated by commas. Report you counts for the five trials with car going in the opposite direction in the second line below, separated by commas.
15 counts 41 cm, 14 counts 35 cm, 16 counts 48 cm, 12 counts 30 cm, 10 counts 24 cm
11 counts 22 cm, 18 counts 48 cm, 16 counts 40 cm, 19 counts 55 cm, 8 counts 19 cm
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Report the five resulting accelerations for the first direction in the first line below, separated by commas, and use the same format to report in the second line the five for the second direcion. Starting in the third line show the details of how you found one of your accelerations.
9.3 cm/s^2, 8.9 cm/s^2, 9.4 cm/s^2, 10.4 cm/s^2, 12 cm/s^2
9.1 cm/s^2, 7.2 cm/s^2, 7.8 cm/s^2, 7.6 cm/s^2, 15 cm/s^2
Knowing that each one of my counts is approximately 0.2 s, I used that information to find the Vave for each trial. Trial 1-15 counts is approx. 3 seconds. Vave= 41 cm/3 s=14 cm/s Using Vave, I could determine that Vf is 28 cm/s. A=28cm/s/3s= 9.3 cm/s^2
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How far from the lower end of the ramps did you have to position the two balls in order to synchronize their consecutive time intervals with the time interval for the third ball released from rest at the top of the third ramp?
The two lower balls were approximately 6.5 cm from the lower end of the ramp.
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You didn't time the intervals for either trial. Suppose that the ball on the third ramp required 3 seconds to travel the 30-cm length of that ramp. What was the acceleration of that ball? Report the acceleration in the first line. Explain how you found it starting in the second line.
vAve=30/3=10cm/s. Vf is 20 cm/s A=20 cm/s/3 s= 6.7 cm/s^2
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Assuming the 3-second interval for the ball on the third ramp, what was the time interval for ball released on the first ramp, and what was the resulting acceleration? Report the acceleration in the first line, and explain how you calculated it starting in the second line.
5.7cm/s^2
I begin with 1.5 seconds, assuming that the 2 balls take half the time each of the third ball to cover the smaller distance. 1.5 seconds to travel 6.5 cm. 6.5cm/1.5 s=4.3 vAve. Vf=8.6. A=8.6 cm/s/1.5s=5.7 cm/s^2
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Are your two results for the accelerations reasonably consistent? Why would you or would you not expect them to be so?
They are reasonably consistent. I would expect them to be, but I would expect the acceleration from the third ramp to be slightly higher as it has more time to increase its velocity and therefore overall acceleration.
acceleration on these ramps is unlikely to change with time; constant acceleration means constant acceleration
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Are your results in any way relevant to the problem of ordering v0, vf, `dv, v_mid_x, v_mid_t and vAve? If so, what conclusions can you draw?
I can conclude that v0 is the lowest in this situation and vf is the highest. `dv is close to or equal vf. The order would be as follows, v0, v_mid_t, v_mid_x, vAve, `dv, and vf.
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This problem is optional for Phy 201 students. University Physics students should attempt to solve this problem: Use your knowledge of uniformly accelerated motion to answer the following: If the accelerations are uniform on all three ramps, with all three accelerations being equal, then at what position would the balls on the first two ramps need to be placed in order to achieve the desired result?
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&#This looks good. See my notes. Let me know if you have any questions. &#
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