In an experiment with a semi-circular glass block, a narrow beam of white light which has passed through a red filter is incident radially on the curved face, so that there is no deviation at the curved face.
A students measures the angle of incidence in the glass at the place surface, and the angle of refraction in the air. The results are shown below.
Explain why there would be no refraction for an angle of incidence of 40 degrees.
I know this is to do with total internal reflection, but I've no idea how to word my answer.
It is suggested that using a laser instead of a white light source with filters will produce a more reliable value for the refractive index.
Suggest two advantages of using a laser.
Could someone please help me with this? I'm thinking it is to do with lack of dispersion or refraction that would occur with white light, but I don't actually know if this is the right thinking or how to word an answer.
Suggest one difficulty or disadvantage which might be encountered.
I'm thinking damage to eyes perhaps? How would I word this as an answer?
This is A-level standard. All help is appreciated. Thanks.
Solved it.