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.