In a river 2m deep,a water level measuring post embedded into the river stands vertically with 1m of itabove the water surface.If the angle of inclination of the sun above the horizon is 30*,calculate the length of the shadow of the post on the bottom surface of the river.Refractive index of water is 4/3
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"yes" ?
"No" ?
SURE
The ray of light from the sun touching the top of the post is incident at a distance
1/tan30° = √3 m from the post on the water surface.
This ray then refracts at an angle r given by
sini/sinr = 4/3
=> sinr = (3/4) * sin60°
=> r = 40.5°
=> light ray reaches a distance
= √3 + 2tan(40.5°) m
= 3.44 m.
"No" ?
SURE
The ray of light from the sun touching the top of the post is incident at a distance
1/tan30° = √3 m from the post on the water surface.
This ray then refracts at an angle r given by
sini/sinr = 4/3
=> sinr = (3/4) * sin60°
=> r = 40.5°
=> light ray reaches a distance
= √3 + 2tan(40.5°) m
= 3.44 m.