A lens has a power of +2.0 Dioptre. Which one of the following statements about the lens is true ?
- A.The lens is concave and has a focal length of 0.5 metre
- B.The lens is convex and has a focal length of 2.0 metre
- C.The lens is convex and has a focal length of 0.5 metre
- D.The lens is concave and has a focal length of 2.0 metre
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A positive power means a converging (convex) lens, and f = 1/P = 1/2 = 0.5 m. The power of a lens is the reciprocal of its focal length in metres: P = 1/f. Its SI unit is the dioptre (D), and 1 D is the power of a lens…
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