cq_1_041

Phy 121

Your 'cq_1_04.1' 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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45 min

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The problem:

A ball is moving at 10 cm/s when clock time is 4 seconds, and at 40 cm/s when clock time is 9 seconds.

• Sketch a v vs. t graph and represent these two events by the points (4 sec, 10 cm/s) and (9 s, 40 cm/s).

answer/question/discussion:

• Sketch a straight line segment between these points.

answer/question/discussion:

• What are the rise, run and slope of this segment?

answer/question/discussion:

The rise is aprx 5 sec and the run is about 30cm

The run is five seconds. Be sure you understand what it means to graph y vs. x. The quantity after the 'vs.' is graphed on the vertical axis and the change in this quantity is the rise, not the run. The quantity before the 'vs.' is graph on the horizontal axis and the change in this quantity is the run.

There is no quantity in this problem or on the graph that is equal to 30 cm.

The slope is .1667

The slope of the graph has units which are determined by the units of the rise and the run.

• What is the area of the graph beneath this segment?

answer/question/discussion:

I’m not sure how to give the area of the lower part of the graph.

Is this the area of the slope * `dt*`dt?

I've created a document entitled 'open q_a', which is simply a document with questions and answers. Its suggested use is explained at the beginning of the document.

You should access the document and run through Topic 4. The questions are mostly short and should be easy, and should clarify your thinking on questions of the type asked here.