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example 10.4a
before this it says,
"n1 sin theta 1 = n2 sin theta 2
If n2 > n1, the light ray will bend towards the normal, while if n2 < n1, the lightray will bend away from the normal"
"
Example 10.4a
If the index of refraction doubles for a liquid (in which a coin is submerged), the apparent depth of the coin when viewed from the air above, will:
A. increase,and it appears at a position shallower than its true depth.
B. decrease,and it appears at a position shallower than its true depth.
C. increase, and it appears at a position deeper than its true depth.
D. decrease, and it appears at a position deeper than its true depth.
Solution
Apparent depth is the depth at which you think an object is submerged; it may vary from the object's true depth because of refraction. For example, if you look at a coin in a fountain, you may think the object is higher than it actually is. The real coin is at the bottom; you may think ifs only a few feet from the surface.
Light coming from the surface of the coin bends as it goes from the water into the air (and into your eyes). Because the index of refraction of water is greater than that of air, we can deduce that 8air> 6water, and thus light bends away from the normal. Your brain will think that the coin lies on a direct path from your eye to the coin's apparent position (asshownin the diagram above). This apparent light path (represented by the dashed line) is, however, higher than the true light path; you think that the coin is higher than it truly is. Thus, the apparent depth of a submerged object is less than its true depth. The answer mustbe either AorB.
Now, increasing the refractive index of the liquid medium would only exaggerate the bending. You would then think the apparent depth had decreased (i.e., the coin would appear to be closer to the surface). That rules out choice A and leaves us with choice B. The best answer is choice B."
so i set n1 to be air and n2 to be water. if n2 is higher than n1, shouldn't the light ray bend toward the normal? and also, if it bends to the normal, things will appear deeper? bends away, things will appear shallower?
before this it says,
"n1 sin theta 1 = n2 sin theta 2
If n2 > n1, the light ray will bend towards the normal, while if n2 < n1, the lightray will bend away from the normal"
"
Example 10.4a
If the index of refraction doubles for a liquid (in which a coin is submerged), the apparent depth of the coin when viewed from the air above, will:
A. increase,and it appears at a position shallower than its true depth.
B. decrease,and it appears at a position shallower than its true depth.
C. increase, and it appears at a position deeper than its true depth.
D. decrease, and it appears at a position deeper than its true depth.
Solution
Apparent depth is the depth at which you think an object is submerged; it may vary from the object's true depth because of refraction. For example, if you look at a coin in a fountain, you may think the object is higher than it actually is. The real coin is at the bottom; you may think ifs only a few feet from the surface.
Light coming from the surface of the coin bends as it goes from the water into the air (and into your eyes). Because the index of refraction of water is greater than that of air, we can deduce that 8air> 6water, and thus light bends away from the normal. Your brain will think that the coin lies on a direct path from your eye to the coin's apparent position (asshownin the diagram above). This apparent light path (represented by the dashed line) is, however, higher than the true light path; you think that the coin is higher than it truly is. Thus, the apparent depth of a submerged object is less than its true depth. The answer mustbe either AorB.
Now, increasing the refractive index of the liquid medium would only exaggerate the bending. You would then think the apparent depth had decreased (i.e., the coin would appear to be closer to the surface). That rules out choice A and leaves us with choice B. The best answer is choice B."
so i set n1 to be air and n2 to be water. if n2 is higher than n1, shouldn't the light ray bend toward the normal? and also, if it bends to the normal, things will appear deeper? bends away, things will appear shallower?
