:p

4 images for prashants q

No Voters?

[2] [2] [2] [2] [2]

I am very sure answer is 3

How U r that sure... ???

vote for six..

have reasons...

!!

confusing!

no more comments...

Final answer, anyone?

nishant bhaiya will give a complete explanation with answer once he comes back from his "winter vaccations" :P

OK. Deciding the answer by votes.

For your favourite number of images, type NoI followed by your choice for the number of images(x)

******Conditions********

x ε Z⁺

Final answer, anyone?

however for iit exam ans 3 does fine cos we always use straight screen

I think Nishant's explanation is perfect. There will be 3 sharp images formed in a fuzzy background.

Explanation is very simple. From Aragorn's image, any part of the lens having the same μ will focus the light at the same point, thus forming 3 sharp images. However, if you take rays incident on different μ parts(say μ₁ and μ₂), then their point of convergence will depend on which ray you have chosen. I mean if you take rays incident on different part of the (μ₁ and μ₂), they'll meet at different places hence the fuzziness in the background.

This image might help in giving you the idea of the concept

How about a type of lens which has different materials, which is symmetrical about the principal axis? Like the one shown

THanks for the diagram sir. Have you seen this thread
http://targetiit.com/iit_jee_forum/posts/colours_again_961.html?
PLs reply to that question. [1]

thanks for the explanation , i got carried away by the fact that an image is formed if just 2 rays intersect at a point

Same here. I also felt that img is formed whenever any 2 rays intersect!

For Prashant Bhaiyyah's question, 4 distinct and sharp images will be formed if an object is kept before it [4]

Is'nt 3 the answer??

I don't know, Akshay[2]. I just thought of this question and posted it.

It has to be 3,if the materials have different μ