Light - Physics

bonkysleuth SG

The diagram shows 4 bulbs in front of a plane mirror. The cardboard blocks the observer from direct views of the bulbs. Which of the bulbs can be seen by the observer?

By drawing the light rays (I did so to double-check my answer), I discovered that it is possible for the observer to see light bulb A. However my answer on the assessment book says C. I did this question in school below and if I did not forget, the answer should be A. Not sure about this. Someone, please come forward to help.thank you

bonkysleuth SG

A and D are supposed to be a semi-circle. Anyway, the incorrect diagram is A. But is the reason due to the fact that we do not know the critical angle and thus we can't tell whether the angle of refraction is 90 deg? Or is there any other reasons?

Audioboxing SG

I'll respond to the 2nd query about the glass block thingy.

Since the light ray is traveling from air to glass, A is physically not possible since the angle of refraction is larger than the angle of incidence.

Regarding the 1st post on mirrors,

Sometimes the print may not be accurate. As long as you know how to do that's fine already. Just my opinion...

Garrick_3658 SG

Since the light ray is traveling from air to glass, A is physically not possible since the angle of refraction is larger than the angle of incidence.

Because refractive index of glass is greater than 1.

I think I'll leave drawing issues to eagle or anybody else who can draw on com.

eagle SG

The diagram shows 4 bulbs in front of a plane mirror. The cardboard blocks the observer from direct views of the bulbs. Which of the bulbs can be seen by the observer?

Probably your assessment is wrong

eagle SG

If u travel from a optically less dense medium to a optically denser medium, there cannot be total internal reflection. Furthermore, the light ray should bend towards the normal. In the case of A, the light ray actually bend away from the normal.