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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.
** CQ_1_03.1_labelMessages.txt **
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):
v_ave = ‘ds/’dt =30 cm / 5 s = 6 cm/s
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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):
v_ave = (v_f + v_0)/2 solve for v_f and get v_f=2*v_ave - v_0 or since we know v_0 = 0 then v_f = 2*v_ave so v_f = 6 cm/s * 2 = 12 cm/s
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• By how much did its velocity therefore change?
answer/question/discussion: ->->->->->->->->->->->-> (start in the next line):
+ 12 cm/s
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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):
a_ave=’dv/’dt = 12 (cm/s)/5s = 12/5 cm/s^2 = 2.4 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):
Starts at the origin and increases at an increasing rate or concave up.
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The velocity changes at a uniform rate, so the v vs. t graph would be linear, increasing at a constant rate.
The position vs. t graph would be concave up (increasing at an increasing rate).
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&#Your work looks good. See my notes. Let me know if you have any questions. &#