At age 16, a girl requires eye glasses with lenses of 2 dioptres in order to read a book at 25 cm. At the age of 32, she finds that while wearing these glasses she must hold a book 40 cm away from the eyes. What power lenses does she require at this age to read a book at 25 cm-
Text Solution
Verified by ExpertsThe correct answer is:
C
= 
⇒ v = – 200 cm
= 
– 
= 
P = 
= 3.5 dioptre
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