1) a) angle of reflection = angle of incidence so your answer will be the same (47.5) b) use Snell's law to answer this part sin i /sin r = refractive index. angle of incidence = 90 - 47.5 = 42.5 sin r = sin 42.5/1.66 I'll let you do the calculator button pressing you can then easily calculate the angle between surface and ray. to answer Qs 2 and 3 you will need to do the same thing. have fun working them out. Actually you may want to check whether this is a trick question . The angle of incidence may well be over the critical angle (c)- in which case the refracted angle will be 90 so angle with glass is zero. 1/sin c = refractive index sin c = 1/1.66 c = sin ^-1 1/1.66) . Comes to about 37 degrees so it will reflect off!!
124) A parallel beam of light in air makes an angle of 47.5°°with the surface of a glass plate having a refractive index of 1.66. What is the angle between the reflected part of the beam and the surface of the glass?
47.5°
Related Optics MCQ with Answers
66°
1) a) angle of reflection = angle of incidence so your answer will be the same (47.5) b) use Snell's law to answer this part sin i /sin r = refractive index. angle of incidence = 90 - 47.5 = 42.5 sin r = sin 42.5/1.66 I'll let you do the calculator button pressing you can then easily calculate the angle between surface and ray. to answer Qs 2 and 3 you will need to do the same thing. have fun working them out. Actually you may want to check whether this is a trick question . The angle of incidence may well be over the critical angle (c)- in which case the refracted angle will be 90 so angle with glass is zero. 1/sin c = refractive index sin c = 1/1.66 c = sin ^-1 1/1.66) . Comes to about 37 degrees so it will reflect off!!
2.51??108ms?1
use snell's law
58.1?
Angle of reflection = angle of incidence (B) Use Snell's law. n1/n2 = sin(theta1)/sin(theta2) But in order to use snell's law, you need to get the ratio of n's first. You can do that, though, using the fact that light incoming at the critical angle refracts at 90 degrees. n1/n2 = sin(critical angle)/sin(90 degrees)= sin (critical angle) Therefore, for your answer to part (B) sin (refracted angle) = sin (incident angle)sin(critical angle).
22.8°
Angle of reflection = angle of incidence (B) Use Snell's law. n1/n2 = sin(theta1)/sin(theta2) But in order to use snell's law, you need to get the ratio of n's first. You can do that, though, using the fact that light incoming at the critical angle refracts at 90 degrees. n1/n2 = sin(critical angle)/sin(90 degrees)= sin (critical angle) Therefore, for your answer to part (B) sin (refracted angle) = sin (incident angle)sin(critical angle).