Question

plz anyone explain me the sum

Answer 1

once check out all the formulas...so that you can solve this problem easily....
so
here the sum is to find the speed of light in a medium,..but they haven't given a specified medium...we already know about The critical angle..right? critical angle is the angle of incidence beyond which the total internal reflection takes place..here the given critical angle is 49 degrees...
the speed of light was already given in the question...3.00×100000000 m/s.....this is the speed of light in vacuum....finally,this hey have asked about the speed of light when the critical angle is 49 degrees...and once you clearly understand the question then the answer will be understood easily....try to understand the solution now...hope you have understood the question...thank you......