Post a New Question

Physics...please help

posted by .

A beam of light passes from air to ethanol, with index of refraction of 1.36. If the angle of incidence ( 1) is 30.0 degrees, then calculate the angle of refraction, after light passes through ethanol and enters into air.
A. 15.3 degrees
B. 21.6 degrees
C. 30.0 degrees
D. 39.8 degrees

I tried it and got C??

  • Physics...please help -

    its B

  • Physics...please help -

    The answer can be found using the following method:

    Index of refraction 1[wtf is this?: air = 1.00] * Sin(30)[wtf is this?: 30 degrees]
    all of that is equal to =
    Index of refraction 2[wtf is this?: 1.36 {water is 1.33 just fyi}] * Sin(??) [wtf is this?: what you are asked to find]

    Okay now that I've laid that out for your lazy procrastinating undisciplined drudering self:

    1.00 * Sin(30) or 1.00 * 0.5, because the Sin(30 degrees) = 0.5
    So the 1.00 * 0.5 = 1.36 * some number that is the same as saying Sin(??some angle??)

    Let me grab my graphing calculator you slovenly procrastinating not doing what you are supposed to person...
    (1.00*0.5)/1.36 = 0.3676470588
    That isn't the angle you are looking for.
    Remember how I took the sin of 30 degrees and got 0.5? This last number is the same kind of dude. We have to Sin^-1(0.3676470588) to find our angle. [WTF does that mean?: it means inverse Sin (bla number) = an angle]
    And just you know, since you don't study like you should, that bla number is actually a fraction between 0 and 1 which represents the height of the triangle in a unit circle. If you don't know wtf that is, you need to catch up and handle yourself, or you're going to be very disappointed in yourself soon...


Answer This Question

First Name:
School Subject:

Related Questions

More Related Questions

Post a New Question