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JEE Main202124 Feb 2021Morning ShiftPhysicsRay OpticsActual

The focal length f is related to the radius of curvature r of the spherical convex mirror by:

Options

  1. Af = - 1 2 r
  2. Bf = + 1 2 r
  3. Cf = r
  4. Df = - r

Correct answer

B. f = + 1 2 r

Step-by-step solution

For convex mirror, focus is behind the mirror. As we can see from the figure that, ⇒ f = + r 2

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