COMEDK · Physics · 25. Ray Optics
When a particular wave length of light is used the focal length of a convex mirror is found to be \(10 \mathrm{~cm}\). If the wave length of the incident light is doubled keeping the area of the mirror constant, the focal length of the mirror will be:
- A 20 cm
- B 5 cm
- C 10 cm
- D 15 cm
Answer & Solution
Correct Answer
(C) 10 cm
Step-by-step Solution
Detailed explanation
The focal length \(f\) of a spherical mirror is given by the relation \(f = \dfrac{R}{2}\), where \(R\) is the radius of curvature of the mirror. The radius of curvature \(R\) depends only on the geometry and the physical dimensions of the mirror surface. It is determined by the…
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