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