Summary of using a laser and soap water study refraction of light
Answers
As shown in figure, laser light is made to incident on a transparent glass container that has soap solution.
Laser light beam as indicated AC in figure, refracted and emerges at opposite side at E.
A screen is placed in front of the container to capture the laer spot. Distance AB, ie distance between
beam exit point at laser and the container is measures.
Distance BC, distance between laser beam incident point at container and a point B which is exactly at the
horizontal level of laser exit point is also measured.
we have BC/AB = tan i , where i is angle of incidence.
Similarly, distance EG, distance between point of emergence of laser beam at the container and screen is measured.
Distance GF, distance between laser spot at screen and the point G in scren which is exactly at horizontal level of E is measured.
we have FG/GE = tan e, where e is angle of emergence.
A point D is marked at the container just opposite to C. Distances DE and CD ( container diameter ) are measured.
we have, DE/CD = tan r, where r is the angle of refraction.
from the measured distances, angles i, r and e are calculated.
then refractive index of soap solution = sin i / sin r = sin e/ sin r
