{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

990_Physics ProblemsTechnical Physics

990_Physics ProblemsTechnical Physics - Chapter 35 P35.42(a...

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
Chapter 35 331 P35.42 (a) sin sin θ θ 2 1 2 1 = v v and θ 2 90 0 = ° . at the critical angle sin . sin 90 0 1 850 343 ° = θ c m s m s so θ c = = ° sin . . 1 0 185 10 7 a f . (b) Sound can be totally reflected if it is traveling in the medium where it travels slower: air . (c) Sound in air falling on the wall from most directions is 100% reflected , so the wall is a good mirror. P35.43 For plastic with index of refraction n 1 42 . surrounded by air, the critical angle for total internal reflection is given by θ c n = F H G I K J F H G I K J = ° sin sin . . 1 1 1 1 1 42 44 8 . In the gasoline gauge, skylight from above travels down the plastic. The rays close to the vertical are totally reflected from the sides of the slab and from both facets at the lower end of the plastic, where it is not immersed in gasoline. This light returns up inside the plastic and makes it look bright. Where the plastic is immersed in gasoline, with index of refraction about 1.50, total internal reflection should not happen. The light passes out of the lower end of the plastic with little reflected,
Background image of page 1
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}