Your 'cq_1_6.1' 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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For each situation state which of the five quantities v0, vf, `ds, `dt and a are given, and give the value of each.
A ball accelerates uniformly from 10 cm/s to 20 cm/s while traveling 45 cm.
v0 = 10cm/s, vf = 20cm/s, and `ds = 45 cm
A ball accelerates uniformly at 10 cm/s^2 for 3 seconds, and at the end of this interval is moving at 50 cm/s.
a = 10c/s^2, `dt = 3s, and vf = 50cm/s
A ball travels 30 cm along an incline, starting from rest, while accelerating at 20 cm/s^2.
`ds = 30cm, v0 = rest (0cm/s), and a = 20cm/s^2
Then for each situation answer the following:
Is it possible from this information to directly determine vAve?
Yes to all 3 situations. With any 3 of the quantities listed above, we can solve for the other 2 quantities, and since we can
solve for the other 2 quantities, we can find the value of the vAve.
In the third situation you know v0, a and `ds. You can't directly reason out anything from these quantities. To use the definition of vAve you would need to know either vf (to be used with v0) or `dt (to be used with `ds). To use the definition of aAve you would have to know either vf (to be used with v0 to find `dv, so that you have a and `dv) or `dt (with a and `dt you can find `dv, then from v0 can find vf).
You can use the third or fourth equation of motion so get a result, but such a solution would use an equation whose intuitive meaning is not directly clear, and so does not constitute direct reasoning.
You cannot directly determine all quantities in situation 3. You need to use the equations of motion.
Is it possible to directly determine `dv?
Yes to all 3 situations. With any 3 of the quantities listed above, we can solve for the other 2 quantities, and since we can
solve for the other 2 quantities, we can find the value of the `dv.
The use of equations does not constitute direct reasoning. You can't find `dv from the given information using direct reasoning.
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20 min.
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Please respond relative to goal of C.
&#Good work. See my notes and let me know if you have questions. &#