PASCO OS-8536 OPTICS TABLE - Manual (Page 19)

15
012-06557A Optics Table
Teacher’s Guide
Experiment 1: Reversibility
Suggestions on Procedure
For best results, make sure that the Cylindrical Lens is aligned exactly with the Ray Table.
The index of refraction is equal to the slope of the “Refraction 1” graph. n = 1.498
The slope of data set 2 is 1/n. Thus, n = 1.501.
Yes, the Law of Refraction is the same for light rays going in either direction between the two media..
Yes, the principle of optical reversibility holds for reflection as well as refraction.. The angle of incidence
equals the angle of reflection regardless of which side the light is coming from.
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
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
Sin(angle of incidence)
Sin(angle of refraction)
5 Refraction 1
2 Refraction 2
slope = 1.498
slope = 0.6662
1/slope = 1.501
Experiment 2: Dispersion
Color separation was first noted at about 40°, although it may be noticeable before then depending on the light
in the room.
Maximum separation occurs at about 85°; beyond that the violet is totally internally reflected.
In order: (although not all colors may be resolvable depending on the room light) red, orange, yellow, green,
cyan, blue, violet.
With an incident angle of 40°, the violet was at 76° and the red was at 73°.
n
red
= 1.488
n
violet
= 1.510
Experiments 3 through 9
Please refer to the Instruction Manual and Experiment Guide for the OS-8515 Basic Optics System.