# A physics challenge...

Let us suppose that a person seating opposite to you at the table wears glasses. Can you determine whether the person is near-sighted or far-sighted.

Assumptions :-

Being a polite person, you would not ask that person to take out his glasses so that you can experiment on it.

Note by Tushar Gopalka
6 years, 3 months ago

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I will point a gun coloured like chocolate from 100 yards away, if he realises its a gun, then the glasses are either sun glasses or for seeing close objects, if he instead comes close thinking its chocolate, and later realises and runs,, then the opposite ,

Just kidding, i am not so cruel i will simply shoot him and check his glasses, whether convex or concave ,

Ok on a serious note, i liked ronak aggarwals idea,,

- 6 years, 3 months ago

Good sense of humour! :D

- 6 years, 3 months ago

Yeah and that is the true solution. Try it on someone and it indeed is true but effects are measurable only if power is high

- 6 years, 3 months ago

Check his glasses. The kind of glasses he is wearing depends on whether he is near-sighted or far-sighted. Concave lens would mean he is near-sighted while convex would mean he is far-sighted.

- 6 years, 3 months ago

How will you check the glasses, without touching. That is the basic question.

- 6 years, 3 months ago

Can't we simply watch the eyes of the person whether they are enlarged or contracted then determine whether he is near sighted or far sighted.

- 6 years, 3 months ago

Right, simple and easy and yet most people fail to answer this. Though its right, Make your answer more scientific, ronak.

- 6 years, 3 months ago