Data Page

In the following table cutoff voltage is measured in volts and time is measured in seconds. 3RD TRY Data 20% redo Color      cutoff(V)    time1  time2   time3   time4   time 5 Yellow      0.70        8.25   8.75    9.20    9.06     9.28 Violet      1.42      16.50   19.06   19.30   17.12    16.80 Data 40% redo Color      cutoff(V)    time1  time2   time3   time4   time 5 Yellow      0.70        8.00   8.42    6.72    8.75     7.59 Violet      1.42        8.72   9.68    9.68    9.75     8.84 Data 60% Color      cutoff(V)    time1  time2   time3   time4   time 5 Yellow      0.70        6.66   5.25    6.00     5.06    5.75 Violet      1.42        7.06   7.66    7.31     6.97    7.19 Data 80% Color      cutoff(V)    time1  time2   time3   time4   time 5 Yellow      0.70        4.37   5.19    4.13     4.25    4.03 Violet	    1.42        4.41   5.44    5.22     5.25    5.46 Data 100% Color      cutoff(V)    time1  time2   time3   time4   time 5 Yellow      0.70        3.69   3.50    4.28    4.50     4.19 Violet      1.42        4.88   4.56    4.44    4.62     4.65

We make measurements of stopping potential of the first and second order light bands according to the diagram on pg.38 of the procedure. •	First Order 1st run Color           max(V) Ultra-Violet   2.030             As we turn the apparatus from UV to Violet we notice that V drops from Violet         1.515             2 to about 1.7 in between and then down to 1.5 on Violet. Past violet V Blue           1.707             rises again to 1.7. This is contrary to our expectations. Yellow         0.720 with filter, 1.335 without Green          1.234 with filter We realize by closer inspection of the diagram in the procedure that we in fact were not measuring the first order light bands, so we redo the measurements at what we now believe to be the first order set of bands. This explains why the yellow line came before green and why “blue” had higher stopping voltage than “violet”. •	First Order (redo) 1st run Color          max(V) Ultra-Violet   2.064 Violet         1.718 Blue           1.493 Green          .849 with filter, 1.007 without Yellow         .717 with filter, 1.053 without Now we move to second order bands. •	Second Order 1st run Color          max(V) Ultra-Violet   2.062 Violet         1.731 Blue           1.520 Green          1.242 with filter, 1.335 without Yellow         0.735 with filter And the process is repeated. •	First Order 2nd run Color          max(V) Ultra-Violet   2.069 Violet         1.725 Blue           1.495 Green          0.850 with filter Yellow         0.714 with filter •	Second Order 2nd run Color          max(V) Ultra-Violet   2.061 Violet         1.725 Blue           1.515 Green          1.242 with filter Yellow         0.735 with filter


 * Trial 4 First Order:(Formal set)

Yellow: .713

Green: .845

Blue: 1.488

Violet: 1.669

Ultra Violet: 2.009


 * Trial 5 First Order:(Formal set)

Yellow: .710

Green: .841

Blue: 1.480

Violet: 1.705

Ultra Violet: 2.045


 * Trial 6 First Order:(Formal set 20% Intensity)

Yellow: .707

Green: .840

Blue: 1.480

Violet: 1.696

Ultra Violet: 2.035


 * Trial 6 First Order:(Formal set 60% Intensity)

Yellow: .707

Green: .842

Blue: 1.481

Violet: 1.704

Ultra Violet: 2.035