ShmoopTube

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Thank you here's your shmoop toos your brought to you

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by contact lenses which help us see the world clearly

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except for when they slide apart eyeballs and feel like

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they have lodged in our brain And we have to

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spend an hour trying to dig them out All right

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well there are a few reasons Contact lenses They're difficult

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to see when placed in saline solution For one the

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person who just took him out is well blinder than

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usual Some other possibilities Heir listed below Which of the

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following statements is true Select too Well ah yes it's

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your favorite morning ritual sloshing our finger in the contacts

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case when we're half blind half a way we can

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and trying to find the lenses are but let's take

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a closer look at this question We can seek contact

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lenses when we're putting them in because in air they've

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been the light that hits him so we can see

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where the edges are Well in saline solution the borders

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aren't is easy to see that's not because the radio

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of curvature change though that's just part of the lenses

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shape and it's not affected by the environment So a

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is a correct answer now to determine if the effect

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of focal length is longer Well let's look at the

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lens makers equation when we have a lens in air

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with lens makers equation shows that the reciprocal of the

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focal length equals the refractive index of the lens minus

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one times the difference between the reciprocal of the radius

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of lens side closest to the light source and the

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radius of the lens side farthest from the light source

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All right in the air these numbers won't change the

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ready I remain the same refractive index remains the same

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air is air so that's not going to change But

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when a lens isn't in the air and it's in

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a different medium like oh say saline solution while then

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the equation changes instead of the refractive index minus one

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we use the refractive index of the lens over the

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refractive index of the medium The lens is in minus

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one because pretty much everything has a refractive index larger

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than one result of this new equation will show a

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longer focal point than for a lens in the air

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So be is also correct As we can see in

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these equations The refractive index of lens doesn't change no

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matter what material it's in that's something that's inherent in

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what the lens is made up It's not like dunking

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an oreo and milk and watching it get all soft

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and gooey and stuff i'm sorry we're feeling snacky here

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All right Well the refractive index stays the same in

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air water oil or well anything Soc is incorrect and

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transparency is also an inherent quality The environment that the

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lenses in doesn't change the lens itself So d yeah

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that's wrong too if you're like Us and blind as

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a bat without your contacts Well next time you stumble

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into the bathroom in the morning and try to regain

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the power of sight Remember that it's physics that it's

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making it so hard to get those stupid little lenses 00:02:57.37 --> [endTime] No sorry we're not morning people

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