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4 Feb 2010 10:49:36 IST

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under what condition does a lens immersed in a liquid becomes invisible?(a) the refractive i

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under what condition does a lens immersed in a transparent liquid becomes invisible?(a) the refractive index of the material of lens IS GREATER THAN the refractive index of the liquid(b) IS LESS THAN(c)IS EQUAL TO(d)IS GREATER THAN OR EQUAL TO

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winx

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5 Feb 2010 09:55:14 IST

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waitin 4 sum rplyyyyy

AIR 538 Asish

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5 Feb 2010 10:19:35 IST

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is it (c) or (d) ?

winx

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5 Feb 2010 10:26:37 IST

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i duno the answer

dis is nstse-2010 (unified council) question.......m confused wid d options

Transmigrator

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5 Feb 2010 10:54:33 IST

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Its (c) since if the refractive indices of the lens and the liquid are equal, there would be no bending of light when it travels from the lens to the liquid and both will start behaving as if they are same entities..............Hence, the effect of the lens would dissapear or we can say that the lens dissapears..............

winx

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5 Feb 2010 17:14:59 IST

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THANX

SRIJAN MISHRA

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14 Feb 2010 22:46:25 IST

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It is option (c)

Sindhura K

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17 Feb 2010 10:51:49 IST

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yaa it has to be equal......m not sure it bcums invisibl thn.....but i guess it has a chance of being invisible only in tht case

idk idk

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6 Mar 2010 16:33:07 IST

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under any media, the substance with same refractive index will be invisible.

ayush kesarwani

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6 Mar 2010 18:13:30 IST

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(C) because the light becomes undeviated or non refracted which makes the site of view exactly the same as it was before. Hence the lens becomes invisible.

rajnesh chaurasiya

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6 Mar 2010 18:43:40 IST

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it must be equal we are here concerned with visibilty of lens or not greater index cause image shift i

Dharav Solanki

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6 Mar 2010 20:19:25 IST

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The question has already been answered. I'd like to add a few comments here. Why do you see a certain object? Answer this one. And then, answer this question - why are you able to see a certain transparent medium in air even though it is supposed to be transparent?The answer to the second question is refraction. Refraction leads you to view distorted images of the things lying on the other side of the liquid which makes you realize that there is something where the liquid is.Now, answer one little question for me - once you realize this small fact - how is it so difficult to answer this question? Does it become some sort of a thought that, yes, i need some minimal levels of preparation before i can attempt this subject? Get Over It! Whatever you are doing, you are doing it now!

Sarthak Verma

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6 Mar 2010 21:14:42 IST

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its (c), already been given in ncert, check out solved example....

winx

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8 Mar 2010 14:03:45 IST

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actually sumtyms it so happens dat brain cease 2 reason out simple things RATHER DAN DIFFICULT ONES.............

itz human tendency 2 conc on difficult things rather dan easy ones................or in other wurds overlookin easy things .................

dat waz probably da reason y i confused myslf so much........while givin xam n while posting dis EASY question..............

for wch i reasond out da ans............ la8r.......aftr posting questn over here....................

weras dis r da simple things dat matters .............thanx 4 reminding me dis Dharav sir

nyways thanx 4 all who replied......................m satisfied wid al da answers

thanx once again

Bhanu swami

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24 Mar 2010 12:47:28 IST

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its csame refractive index will not let light to bend so observer will not be able to identify the object.

pradeep rout

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29 Mar 2010 10:08:55 IST

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ans. is option (c)IS EQUAL TO

||Mr.Insomaniac||

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30 Mar 2010 22:52:13 IST

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Ans is (c)

Because 1/f=(u_2-u₁)/R

So to make the lens invisible the focal length must be zero

so to refractive index must be zero.

u_2-u₁is =0 if both are equal

zafar haider

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30 Mar 2010 22:54:45 IST

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Whaen refractive index of both the medium will be same

rohit dhingra

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31 Mar 2010 10:52:02 IST

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