Lab Execution 3

does any1 know how to solve for R in Non-Ohmic part I assumed i was V/I=R

For the nonohmic part, R is the slope of the graph. Upon placing values in the chart, a graph will be formulated automatically and a y=***.*x number will appear in the left hand corner. The number before the x, you should recall, is the slope. We can say that R is the slope of the graph because In order to determine the slope you are taking the change in y over change in x, or in other terms, voltage/current.

anyone know how to calculate the error of R for the nonohmic part? it says to keep guessing but I dont know how to go about it..i tried a bunch of thigns but it doesnt work

any one got the error of R for the nonohmic part

I tried a lot of numbers

but nothing worked

(error of r/r) = (error of I/I)
the error of I is given, 0.001 and you measured I and r in lab. Divide error of I by the measured I, then multiply the value by the resistance you got from lab. This would be your error of r. You could use this equation to calculate the error of r for both the execution and analysis part of the lab.

im having trouble gettint the resistance on the second part of the excel sheet with the lightbulb. I tried using all of the formulations for resistance, but nothing gives me the right answer... whats goin on?

For R on the second page, you dont have to calculate it by hand. Go to the last page of the labmanual and it gives you a format to enter into the boxes, which calculates all the values for you

just making sure, for the measured Current I, do we take the given value and mulitply it by 10^-3? (and not 10^-2)

and then for: the measured value of the equivalent series resistance and it's error,
it would be (.001/current)
the error would be (.001/current) * measured resistance?

and then the same procedure for the parallel resistance and error?

just trying to be absolutely sure, thank you so much

For R you take the Voltage/Current.
everything else you said was right

When you guys say we measured current "I" in lab, umm didn't we measure more than one value so which value do I use to figure out the error for R?
Thanks.

For the Execution sheet II, on the bottom it says "Does the calculated value of the equivalent series resistance agree (within error) with the measured value?" What measured value of R is being talked about? Do they mean the R1 and R2 that the TA measured?

Thanks.

That is partially correct. For the in series circuits you do R = R1+R2 (where R1 and R2 are the values the TA told you) and for the in parallel circuits you do the 1/R = 1/R1+1/R2 . Those values of R that you then calculate from those equations are the measured values.