cq_1_021

phy 201

Your 'cq_1_02.1' 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 4 cm/sec and ends with a velocity of 10 cm/sec.

• What is your best guess about the ball's average velocity?

answer/question/discussion: **************** With the information given, you would take a direct average of the two velocities given. (4 cm/sec + 10 cm/sec)/(2) = 7 cm/sec.

• Without further information, why is this just a guess?

answer/question/discussion: **************** It’s a guess because you don’t know exactly how long the ball is travelling at these velocities.

• If it takes 3 seconds to get from the first velocity to the second, then what is your best guess about how far it traveled during that time?

answer/question/discussion: **************** I would take the average velocity, 7 cm/sec and know that it moved for 3 seconds, therefore (7cm/sec)*(3 sec) = 21 cm.

• At what average rate did its velocity change with respect to clock time during this interval?

answer/question/discussion: **************** Since it increased by 6 cm/sec and it took 3 sec to do so, I would take the ratio (6 cm/3 sec) = 2 cm/sec. Again, this is only an average since it may have increased faster in the first second than the last second.

Your unit calculations are not completely correct.

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15 min. to read instructions and answer questions.

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Excellent, except for an error in units.

&#At least part of your solution does not agree with the solution and comments given at the link below. You should view the solution at that link and self-critique as indicated there.

Solution

This link also expands on these topics and alerts you to many of the common errors made by students in the first part of this course. &#