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.
I've realised my mistakes now.