course phy 122
i am coming down that way on Wednesday afternoon is there any way i can just pick the lenses and the generator up at the book store?
You can get the lenses, but first you need to send me a list of what you have received. I would also need to coordinate with the book store, which might or not not be possible on short notice. It depends on when I receive the list.
Also let me know when you are coming so I can let you know what you can pick up where.
The book store should in any case have generator-capacitor sets available for rental. Call them before you come.
course PHY201
If an object increases velocity at a uniform rate from 8 m/s to 27 m/s in 13 seconds, what is its acceleration and how far does it travel?Average acceleration = (27m/s ?8m/s)/13s = 19m/s/13s = 1.5m/s/s
The fianl speed was 1.5m/s/s * 13s = 19.5m/s, so the average speed was = ?*(1.5 * 13) = 9.75m/s
The equation you quote does not give the average speed.
So s = ?acelleration *(time) = ?* 1.5m/s/s * (13s) = ?* 1.5 * 13 = 123.5m
This equation is not valid in this situation. The equation you use applies only when the initial velocity is zero.
Sketch a velocity vs. clock time graph for an object whose initial velocity is 8 m/s and whose velocity 13 seconds later is 27 m/s. Explain what the slope of the graph means and why, and also what the area means and why.
The slope of the graph represents the average acceleration because average acceleration = change in average velocity/change in clock time.
The area represents the distance traveled.
If you calculated the area of this trapezoid, you came out with a result different than the one you obtained for the problem. The slope would agree, up to round-often error.
&#Please see my notes and submit a copy of this document with revisions and/or questions, and mark your insertions with &&&&. &#
&&&&.&# Revision
Average acceleration = ?v / ?t = (27m/s ?8m/s) / 13s = 19m/s /13s = 1.5m/s/s
Vavg = (vf + v0) /2 = (27m/s + 8m/s) /2 = 35/2 = 17.5m/s
Since vavg = ?s / ?t solve algebraically for ?s = ?t * vavg
?s = 17.5m/s * 13s = 227.5m
Good solution.