Physics
Grade-10
Easy
Question
The focal length of a concave lens whose radius of curvature is 26 cm is ____ cm.
Hint:
For a concave lens , focal length f= R/2
The correct answer is: 13
The focal length of a concave lens whose radius of curvature is 26 cm is 13 cm.
- The focal length of a concave lens is half of its radius of the curvature.
- Focal length f= R/2
- When the R is 26 cm, the focal length is 26/2= 13 cm.
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