PASCO OS-8500 INTRODUCTORY OPTICS SYSTEM - Manual (Page 61)

012-02744K Introductory Optics System
®
55
➂
It is. The graph comes out completely linear, which
means that there is a direct proportionality.
➃
n = 1.50
Answers to – Questions
➀
The beam tends to spread out more on the larger
angles, due to the wider area of incidence on the
flat side of the lens.
➁
Some was reflected. This reflected light could be
used to verify that the lens was aligned correctly
with the ray table by noting whether the angle of
refraction was the same as the angle of incidence
on the ray table.
➂
If there is a systematic error, it is likely to be can-
celled by measurements taken on opposite sides.
Exp 5: Reversibility
Suggestions on – Procedure
For best results, make sure that the cylindrical lens is
aligned exactly with the ray table.
Angle of:
Incidence1 Refraction1 Incidence2 Refraction2
0 0.0 0.0 1.0
10 7.0 7.0 7.5
20 13.5 13.5 19.5
30 20.0 20.0 30.0
40 25.5 25.5 39.0
50 31.0 31.0 49.0
60 35.5 35.5 59.0
70 39.5 39.5 70.0
80 41.0 41.0 77.0
➀
The index of refraction is equal to the slope of the
“Refraction 1” graph. n = 1.498
➁
The slope of data set 2 is 1/n. Thus, n = 1.501.
➂
Yes.
➃
Drawings will vary.
➄
Yes. The angle of incidence equals the angle of
reflection regardless of which side the light is com-
ing from.
5
5
5
5
5
5
5
5
5
2
2
2
2
2
2
2
2 2
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1
5 Refraction 1
2 Refraction 2
slope = 1.498
slope = 0.6662
1/slope = 1.501
Sin (angle of incidence)
Sin (angle of refraction)