Physics
Grade-10
Easy
Question
The focal length of a concave lens whose radius of curvature is 76 cm is ____ cm.
Hint:
For a concave lens, the focal length is half of the radius of curvature i.e f= R/2
.
The correct answer is: 38
The focal length of a concave lens whose radius of curvature is 76 cm is 38 cm.
- The focal length of the lens is the distance of the focus from the optical center
- And focal length is half of the radius of curvature.
- The focal length can be calculated by the formula f= R/2
- If the radius of the curvature is 76 cm, the focal length is 76/2= 38 cm.
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