An optical fiber made of glass with an index of refraction 1.50 ...

[DelorasTo]

An optical fiber made of glass with an index of refraction 1.50 that is coated with a material with index of refraction 1.30 has a critical angle of
 
  A) 90.
  B) 41.8.
  C) 60.0.
  D) 50.2.
  E) This combination will not work.

Question 2

Consider 550. nm light passing through 2 narrow slits 2.10 micro-meters apart. The 1st and 2nd order fringes are 1.00 mm apart on a distant screen. How far apart are the 2nd and 3rd order fringes?
 
  A) 1.35 mm
  B) 1.00 mm
  C) 0.750 mm
  D) 0.500 mm
  E) 1.74 mm

[soda0602]

Answer to Question 1

C

Answer to Question 2

E

[DelorasTo]

Thank you!

[soda0602]

Always glad to help...