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Which one of the following statements is not correct?

Options

  1. AThe radius of curvature of a concave mirror is twice its focal length
  2. BPower of a convex lens is negative and that of a concave lens is positive
  3. CThe radius of curvature of a plane mirror is infinity
  4. DWhen a ray of light passes from an optically denser medium to an optically rarer medium, the angle of refracti

Correct answer

B. Power of a convex lens is negative and that of a concave lens is positive

Step-by-step solution

When the image and object are at the two different sides of a lens the then focal length is positive. When the object and images are at the same side (one side only) then the focal length is negative.

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