A student carried out an experiment to investigate the
refraction of monochromatic light at the boundary between two
transparent media. Their results are shown on an additional sheet
provided, which is drawn exactly to scale. Rays A-G on the left of
the diagram show light inside medium 1 incident upon the boundary,
rays A'-G' on the right show the corresponding refracted light
inside medium 2.
My tables of results are below:
Θ1 / Θ2 /
sinΘ1 / sinΘ2
A - 10 / 7 / 0.174 / 0.122
B - 20 / 15 / 0.342 / 0.259
C - 30 / 22 / 0.500 / 0.375
D - 40 / 28 / 0.643 / 0.469
E - 50 / 34 / 0.766 / 0.559
F - 60 / 39 / 0.866 / 0.629
G - 70 / 43 / 0.940 / 0.682
What is meant by monochromatic light?
Single colour/single wavelength. This is my
thinking.
State and explain which medium, 1 or 2 has the
higher refractive index?
I put medium 1 has a higher refractive index as it
refracts the further from the normal line, as my data
suggests.
Plot results. [as above]. Draw graph. [gradient
given below].
I got a graph of sinΘ2 (y-axis) against
sinΘ1 (x-axis) with a gradient of 0.71 using difference in y over
difference in x. What would this gradient represent? I don't think
it is the refractive index as it should be over 1 in that
instance.
The refractive index of medium 1 is given as exactly
1.20. What is the refractive index of medium 2?
I used Snell's Law, but got an answer of
1.71 and I don't think this can be correct as the refractive index
should be less than 1.20 given the refraction shown in the table of
results. I did 1.20 x 0.174 = n2 x 0.122 and isolated n2 to get
1.71 rounded off.
What precision can a protractor be read
to?
I think it is 1 degree.
And what would the uncertainty be based on my
largest value given this precision?
I'm thinking it is 1/70 x 100 = 1.4%
What is meant dispersion?
Seperation of light into its component parts by
refraction. This is my thinking.
State and explain the effect on the accuracy of the
experiment of using white light.
I'm thinking this is something to do with wavelength of
light, but I've not a clue.