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A thin converging lens has a power of 4.0 diopters determined its focal length.

A thin converging lens has a power of 4.0 diopters determined its focal length.
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  • A 2.50m
  • B 0.03m
  • C 5.00m
  • D 0.25m
Correct Answer: Option D
Explanation:
the power of a lens is defined as the reciprocal of the focal length ,expressed in metre.Mathematically, the power of a lens in dioptres is given by:(100)/f(in cm).
thus for lens of power of 4.0 dioptres we have that: (100)/(f) = +4.0
f= (100)/(4.0) = 25cm
= 0.25cm

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