1. Not finding help here? Sign up for a free 30min tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Finding distance by angle of incident

  1. Jul 16, 2013 #1
    1. The problem statement, all variables and given/known data

    The light in a lighthouse sits 55 m above sea level. The beam of light strikes the water
    at an angle of incidence of 630 and illuminates a shipwreck on the ocean floor. If the
    water is 17 m deep, what is the horizontal distance from the lighthouse to the shipwreck?

    2. Relevant equations

    tan=opp/adj

    n1sinθ1=n2sinθ2

    3. The attempt at a solution

    tan63=x/55m

    x=110m

    (1.0)sin(63°)=(1.33)sinθ2

    θ2=42

    tan(42)=opp/17m
    opp=15m

    15+110m=125m
     
  2. jcsd
  3. Jul 17, 2013 #2

    ehild

    User Avatar
    Homework Helper
    Gold Member

    Your method is correct, but you do not get the result with three significant digits if you calculate with two digits. The data are given with two digits, use three during the calculations and round off at the end.

    ehild
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted



Similar Discussions: Finding distance by angle of incident
  1. Incident angle (Replies: 2)

Loading...