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yrelhan4
refraction help?
any ideas about 2nd question. a start will be good.
the formula for radius of the sphere so that no light comes out is R=h/sqrt (mu^2 -1) this might help you.
what aspect of refraction do you not understand.?
|dw:1361076183674:dw| the condition for the source to be JUST seen is that... so find for what radius is that condition satisfied.. once you have what the final radius is... then you can find the time taken to get to that radius!
got it. i was just doing a calculation mistake. thank you anyway.