Physics
Grade-10
Easy
Question
The focal length of a convex lens is 4 m. The power of this lens is ___ D.
- 4
- 0.25
- -4
- -0.25
Hint:
formula of power.
The correct answer is: -0.25
The focal length of a convex lens is 4 m. The power of this lens is 0.25 D.
power=1/4= 0.25D
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