Which direction should you aim to shoot a fish using a laser gun

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When aiming a laser gun at a fish in a lake, one should aim directly at the position where the fish is seen, as the laser light will refract towards the normal line upon entering the water. In contrast, when using a spear or bullet, the aim should be lower than the visible position of the fish due to refraction making the fish appear higher than its actual location. The discussion emphasizes the importance of understanding refraction principles, particularly Snell's law, in determining the correct aim. The consensus is that for a laser gun, aiming at the visible position is correct. This highlights the unique behavior of laser light compared to traditional projectile weapons.
songoku
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Homework Statement
To which direction should you aim your high - power laser gun to shoot a fish in a lake? (You stand on the edge of the lake)
a. the position where you see the fish
b. higher than the position where you see the fish
c. lower than the position where you see the fish
d. depends on the speed of the fish
e. can not be determined
Relevant Equations
Snell's law
If we use a spear or gun with bullet, then we should aim lower than the position where we see the fish because due to refraction, the apparent position of the fish in the lake will be higher (nearer to the surface) than the actual position of the fish.

But if we use a laser gun, I think we should aim to the position where we see the fish because the laser will also be refracted towards normal line when entering the water.

So the answer is (a)

Am I correct?

Thanks
 
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songoku said:
Homework Statement:: To which direction should you aim your high - power laser gun to shoot a fish in a lake? (You stand on the edge of the lake)
a. the position where you see the fish
b. higher than the position where you see the fish
c. lower than the position where you see the fish
d. depends on the speed of the fish
e. can not be determined
Relevant Equations:: Snell's law

If we use a spear or gun with bullet, then we should aim lower than the position where we see the fish because due to refraction, the apparent position of the fish in the lake will be higher (nearer to the surface) than the actual position of the fish.

But if we use a laser gun, I think we should aim to the position where we see the fish because the laser will also be refracted towards normal line when entering the water.

So the answer is (a)

Am I correct?

Thanks
Looks reasonable to me.
 
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Thank you very much
 
Your book has its funny aspects, using high power laser to shoot poor fishes lol.
 
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The book claims the answer is that all the magnitudes are the same because "the gravitational force on the penguin is the same". I'm having trouble understanding this. I thought the buoyant force was equal to the weight of the fluid displaced. Weight depends on mass which depends on density. Therefore, due to the differing densities the buoyant force will be different in each case? Is this incorrect?

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