Problem 5: You can determine the index of refraction of a substance by measuring its critical angle for total internal reection. Randomized Variables {953v : .2 10 Part (a) What is the index of refraction of a substance that has a critical angle of '2.I when submerged in water (with index of refraction 1.333)? Part (D) What would the critical angle be for this substance in air'.' Gm = Problem 6: Consider a camera whose lens has a 4 ' mm focal length. What is the power P, in diopters, of the camera lens\".J P : Problem 7: Some telephoto cameras use a mirror rather than a lens to magnify distant objects. What radius of curvature R, in meters, does the mirror need to have to replace a 55.0 mm focal length telephoto lens? R