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We are given a figure of a half-cylinder with a point a at the top of the half cylinder. Light is transmitted through a half cylinder and the beam was allowed to strike a semi-circular screen.
Question asks : Light that initiates from point a in the figure:
A- will always strike the middle of the screen
B- doesn't leave the half-cylinder disk
C- splits to strike the screen at multiple points
D- slows when leaving the disk and entering air.
Answer is A which does not make sense to me. If Light is hitting the cylinder of different material than air then n is bigger than air. so if it hits the cylinder with an angle of 90 degrees then
n*sin90= nair* sin angle hits the screen
so then for them to be equal the angle can't be 90!
Their explanation is " for light that strikes an interface in a perpendicular fashion it's speed will change but there will be no change in the orientation of the rays"
Thanks a lot!
Question asks : Light that initiates from point a in the figure:
A- will always strike the middle of the screen
B- doesn't leave the half-cylinder disk
C- splits to strike the screen at multiple points
D- slows when leaving the disk and entering air.
Answer is A which does not make sense to me. If Light is hitting the cylinder of different material than air then n is bigger than air. so if it hits the cylinder with an angle of 90 degrees then
n*sin90= nair* sin angle hits the screen
so then for them to be equal the angle can't be 90!
Their explanation is " for light that strikes an interface in a perpendicular fashion it's speed will change but there will be no change in the orientation of the rays"
Thanks a lot!