Optics - Beam illuminating coin under water

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SUMMARY

The discussion centers on the optics problem of determining the angle at which a light beam must be directed to illuminate a coin submerged 1.5 meters under water and 0.90 meters from a side wall. The correct angle relative to the wall for the beam is established as 28.90 degrees, while a participant calculated an angle of 43.29 degrees. The confusion arises from the distinction between reflection and refraction, with participants clarifying that the angle in water is approximately 31 degrees and in air about 43.18 degrees.

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frozen7
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A coin lies on the bottom of a pool under 1.5 m
of water and 0.90 m from the side wall as shown
in Figure 2. If a light beam is incident on the
water surface at the wall,at what angle relative
to the wall must the beam be directed so it will
illuminate the coin. Ans: 28.90

The answer I get is 43.29, different with the given answer? May I know which answer is correct actually?
Thanks.
 
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I don't see a diagram ... but if :
the ray's angle in the water (measured from the vertical) is about 31 degrees,
then the ray's angle in air (measured from the vertical) is about 43.18 degrees.
Are they REFLECTING the ray off the wall? (I expected this to be a refraction)
 

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