Physics307L:People/Trujillo/LAB NOTEBOOK/071010
data for planck's constant
SETTLE VOLTAGE FOR YELLOW ORANGE:=652mV
stop=612mv
1.28s @100%
1.20s @80%
1.72s @60%
2.04s @40%
4.92s @ 20%
SETTLE VOLTAGE FOR GREEN:=800mV
STOP=712mV
1.40s @100%
2.10s @80%
2.50s @ 60%
4.90s @40%
12.0s @20%
SETTLE VOLTAGE FOR BLUE;=1.37V
STOP=1.23V
1.20s @ 100%
2.00s @ 80%
2.00s @60%
2.80s @ 40%
7.40s @ 20%
Settle voltage for purple=1.50V
stop=1.34V
1.28s @100%
1.40s @80%
1.56s @60%
1.92s @40%
5.76s @20%
settle for UV=1.80V
stop=1.62V
6.2s @100%
6.4s @80%
9.7+/-2.0s @60%
17.4s @40%
81s @20%
Data Drocessing
Tomas and I were able to do some first and second order curve fitting on this graph but was not able to get a percise Planks estimation. Our first order looked like 11e-34J. Does not see right..
Methodology
Following instructions in Dr. Gold's lab manual, I made sure the equipment was set up correctly to perform the experiment. First, one should get the light from the lamp as focused as possible by adjusting the diffraction grating/lens. Next, one should make sure light from the lamp reaches the photocathode of the [math]\displaystyle{ \tfrac{h}{e} }[/math] apparatus. How to do this is described in the manual. (perhaps I should upload the manual in case www-hep.unm.edu goes down again) following that, one should test the batteries of the [math]\displaystyle{ \tfrac{h}{e} }[/math] apparatus. I suppose the minimum ratings for the batteries are listed were the apparatus's test points are, so they are +6V and -6V. Measure using a multimeter from the apparatus's ground to each of the battery test points. I measured +8.70V and -8.69V, so the batteries were fine.
