#$&*
PHY 121
Your 'cq_1_04.1' report has been received. Scroll down through the document to see any comments I might have inserted, and my final comment at the end.
** **
cq_1_041
#$&*
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.
** **
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: ->->->->->->->->->->->-> n: ->->->->->->->->->->->-> n (start in the next line):
The graph is a pair of points at 4,10 and 9,40
#$&*
Sketch a straight line segment between these points.
answer/question/discussion: ->->->->->->->->->->->-> n: ->->->->->->->->->->->-> n (start in the next line):
The graph is a line segment with a slope of 6
#$&*
What are the rise, run and slope of this segment?
answer/question/discussion: ->->->->->->->->->->->-> n: ->->->->->->->->->->->-> (start in the next line):
Rise = 30
Run = 5
Slope= 6
&&&&&&&&&&&&&&&&&&&&&&
Rise = 30cm/sec
Run = 5sec
Slope = (30cm/sec)/(5sec)=(6cm/sec)/sec = 6cm/sec^2
&&&&&&&&&&&&&
#$&*
@&
RIse and run have units.
The units of the slope follow from the units of rise and run.
*@
What is the area of the graph beneath this segment?
answer/question/discussion: ->->->->->->->->->->->-> n: ->->->->->->->->->->->-> n (start in the next line):
ave height = 25cm
width = 5cm
area = 25cm*5cm = 125cm^2
&&&&&&&&&&&&&&
Midpoint altitude = 25cm/sec
Area = midpoint altitude * width
= 25cm/sec * 5sec = 125cm
&&&&&&&&&&&&&&&
#$&*
*#&!*#&!
@&
The width of the region is not 5 cm. Check the units.
The 'average altitude' isn't 25 cm. The 'graph altitudes' are not measured in cm.
*@
@&
Your arithmetic and your use of the definitions are fine, but you do need to watch your units.
&#See any notes I might have inserted into your document, and before looking at the link below see if you can modify your solutions. If there are no notes, this does not mean that your solution is completely correct.
Then please compare your old and new solutions with the expanded discussion at the link
Solution
Self-critique your solutions, if this is necessary, according to the usual criteria. Insert any revisions, questions, etc. into a copy of this posted document. Mark any insertions with &&&& so they can be easily identified.If your solution is completely consistent with the given solution, you need do nothing further with this problem. &#
*@
*#&!
@&
Neither axis represents quantities measured in cm, so height ave. height or width would be in cm.
Nor would the area be in cm^2.
*@
*#&!
@&
It shouldn't take you long to do a revision, and if you do I think you'll nail down the very important idea of the units.
&#Please see my notes and, unless my notes indicate that revision is optional, submit a copy of this document with revisions and/or questions, and mark your insertions with &&&& (please mark each insertion at the beginning and at the end).
Be sure to include the entire document, including my notes.
If my notes indicate that revision is optional, use your own judgement as to whether a revision will benefit you.
&#
*@
** **
** **
Revision for Assignment 4 Seed Question 4.1
self-critique rating