A person can see objects clearly only when they lie between \(50\) cm and \(400\) cm from his eyes. In order to increase the maximum distance of distinct vision to infinity, the type and power of the correcting lens, the person has to use, will be:

1. convex, \(+2.25\) D 2. concave, \(-0.25\) D
3. concave, \(-0.2\) D 4. convex, \(+0.5\) D
Subtopic:  Human Eye |
 70%
Level 2: 60%+
NEET - 2016
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The near point of a hypermetropic person is \(75~\text{cm}\) from the eye. What is the power of the lens required to enable the person to read clearly a book held at \(25~\text{cm}\) from the eye?
1. \(+2.67~\text{D}\) 
2. \(-1.25~\text{D}\) 
3. \(-2.67~\text{D}\)
4. \(+1.25~\text{D}\)

Subtopic:  Human Eye |
 67%
Level 2: 60%+
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