Geometrical Optics
The focal length of a concave lens is negative. Therefore, its power should be:
Negative
Positive
Zero
Infinite
Negative
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2 responses to “The focal length of a concave lens is negative. Therefore, its power should be:”
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The focal length of a concave lens is always negative. The negative focal length indicates that the focal point is on the same side of the lens as the incident light, which is a virtual focal point.
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corrected
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