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HELP Stuck on Physics refraction question

Yeh it's question 22 part b :frown: need some help drawing the ray of light it says that the critical angle is less the 45 degrees but not sure where to start :smile: any help would be appreciated thanks :smile: ImageUploadedByStudent Room1365895392.101855.jpg


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(edited 11 years ago)
Reply 1
Original post by That_Clever_Guy
Yeh it's question 22 part b :frown: need some help drawing the ray of light it says that the critical angle is less the 45 degrees but not sure where to start :smile: any help would be appreciated thanks :smile: ImageUploadedByStudent Room1365895392.101855.jpg


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That's strange I posted a thread on the exact same question earlier today, still waiting for a reply hope to get one soon :biggrin:
(edited 11 years ago)
Reply 2
Where did you get that? The diagram doesn't appear to correspond with the text. You should presume that the diagram and text will have been checked and do correspond in real exams.

What you'd do for ray trace type questions do is draw a normal at the point the ray inside the prism meets the next surface and work out it's angle of incidence... It should be clear what to do based on your knowledge of snells law and critical angles.

Refractive index of air is 1.00 unless the question says otherwise.
Original post by Joinedup
Where did you get that? The diagram doesn't appear to correspond with the text. You should presume that the diagram and text will have been checked and do correspond in real exams.

What you'd do for ray trace type questions do is draw a normal at the point the ray inside the prism meets the next surface and work out it's angle of incidence... It should be clear what to do based on your knowledge of snells law and critical angles.

Refractive index of air is 1.00 unless the question says otherwise.


This was in a revision pack from my sixth form :smile: thanks for your help it was the two prisms bit that confused me and thanks again


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