PASCO OS-8515C Basic Optics System - Manual (Page 35)

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M o d e l N o . O S - 8 5 1 5 C E x p e r i m e n t 1 2 : F o c a l L e n g t h a n d M a g n i f i c a t i o n o f a T h i n L e n s
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3. For each intercept, calculate a value of f and record it in Table 12.2.
4. Find the percent difference between these two values of f and record them in
Table 12.2.
5. Average these two values of f. Find the percent difference between this average
and the focal length that you found in Part I. Record these data in Table 12.2.
Analysis Part B: Magnification
1. For the first two data points only (the first two lines of Table 12.2), use the image
and object distances to calculate the magnification, M, at each position of the
lens. Record the results in Table 12.3.
(eq. 12.2)
Table 12.1: Image and Object Distances
Distance from
light source to
screen d
o
d
i
1/d
o
1/d
i
Image Size Object Size
100 cm
90 cm
80 cm
70 cm
60 cm
50 cm
Table 12.2: Focal Length
f
Result from x-intercept
Result from y-intercept
% difference between results from intercepts
Average of results from intercepts
Result from Part I
% difference between Average of results from intercepts and result from Part I
M
d
i
d
o
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⎝ ⎠
⎜ ⎟
⎛ ⎞
– =