Science
If a lens can converge the sun rays at a point 20 cm away from its optical centre, the power of this lens is –
- +2D
- –2D
- +5D
- –5D
Refraction Lens
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Answer
+5D
Reason — Given,
Convex lens as converging rays.
Focal length (f) = 20 cm
P =
Substituting we get,
P = = +5D [positive sign as convex lens.]
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