Class Action Now – law wave reflection
law wave reflection
ScienceMan Digital Lesson – Waves – Law of Reflection
I need help with this refraction problem.?
And please show how you arrived at the answer.
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The laws of refraction and reflection are the
same for sound and for light. The speed of
sound is 340 m/s in air and 1510 m/s in water.
If a sound wave that is traveling in air
approaches a flat water surface with an angle
of incidence of 9.98°, what is the angle of
refraction? Answer in units of degrees (°).
Use Snells Law for refraction for this problem:
let a = incident angle
let b = refraction angle
let v1 = velocity in medium with incident ray
let v2 = velocity in medium with refracted ray
sin a/v1 = sin b/v2
a = 9.98 degrees
v1 = 340 m/s
v2 = 1510 m/s
solve for b
sin(9.8)/340 = sin b/1510
sin b = [1510 * sin(9.8) * 1/340
b = arcsin [1510 * sin(9.8) * 1/340]
b = 49.1 degrees
The angle of refraction is 49.1 degrees
check answer; does sin 9.8 / 340 = sin 49.1 / 1510?
sin 9.8 / 340 = 0.0005
sin 49.1 / 1510 = 0.0005
Filed under Class Action by on Jul 19th, 2011. 