Physics-
General
Easy
Question
Radius of curvature of a concave spherical surface separating air-glass medium is R. A point object is placed on the principal axis in the glass (
= 1.5). For the image to be real, seen by observer in air, distance of the object from P should be :
- 2R < u < 3R
- u < 2R
- u = R
- u > 3R
The correct answer is: u > 3R
For V to be positive
Þ 
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