Phy 201
Your 'cq_1_03.1' 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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The problem:
A ball starts with velocity 0 and accelerates uniformly down a ramp of length 30 cm, covering the distance in 5 seconds.
• What is its average velocity?
answer/question/discussion: ->->->->->->->->->->->-> (start in the next line):
If I travel 30cm in 5 seconds, then my average velocity is going to be 6cm/sec.
30cm/5sec = 6cm/sec
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• If the acceleration of the ball is uniform then its average velocity is equal to the average of its initial and final velocities.
You know its average velocity, and you know the initial velocity is zero.
What therefore must be the final velocity?
answer/question/discussion: ->->->->->->->->->->->-> (start in the next line):
Our final velocity must be 12cm/sec. If our average velocity is 6cm/sec and our starting velocity is 0cm/sec, our formula is final velocity + Starting Velocity/ 2 = average velocity. We know what our starting velocity is and we know our average velocity, so we just have to solve for our final velocity.
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• By how much did its velocity therefore change?
answer/question/discussion: ->->->->->->->->->->->-> (start in the next line):
The velocity changed from 0cm\sec to 12cm\sec
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• At what average rate did its velocity change with respect to clock time?
answer/question/discussion: ->->->->->->->->->->->-> (start in the next line):
With respect to clock time we have a final velocity of 12cm/sec divided by our clock time of 5 seconds and we get an average rate change 2.4 centimeters per second.
good, but units are (cm/s) / s = cm/s^2
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• What would a graph of its velocity vs. clock time look like? Give the best description you can.
answer/question/discussion: ->->->->->->->->->->->-> (start in the next line):
Since we are accelerating at a constant rate then our graph has to be a straight line. The start of the graph will be at point (0,0) and increase at a constant rate until we reach point (5,12). Our graph will have a slope of 2.4 which is also our average rate of change.
be sure you always include the units of every quantity that has units
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30 Minutes
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&#Good responses. See my notes and let me know if you have questions. &#