One of the contests at the school carnival is to throw a spear at an underwater target lying flat on the bottom of a pool. The water is 1.4 m deep. You're standing on a small stool that places your eyes 3.5 m above the bottom of the pool. As you look at the target, your gaze is 35 degrees below horizontal. Your raised arm brings the spear point to the level of your eyes as you throw it, and over this short distance you can assume that the spear travels in a straight line rather than a parabolic trajectory. At what angle below horizontal should you throw the spear in order to hit the target?

Question

anonymous · Answer

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the object seems elevated from O to o' that is were ur eyes are seeing them at first
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so find the refracted angle r made with the vertical(normal N)
then beautifully find i by sini/sinr=refractive index of air with respect to water
that i is angle made with vertical normal
so wat is the angle made with horizontal?

i dont know why they gave height maybe to use this equation:
real depth/apparent depth=refarctive index of water with respect to air