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Question
Fill in the following blank with suitable words :
The reciprocal of the focal length in metres gives you the _________ of the lens, which is measured in ___________.
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Solution
The reciprocal of the focal length in metres gives you the power of the lens, which is measured in dioptres.
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| Column - I | Column - II | ||
| 1 | Retina | a | Path way of light |
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The power of a lens in dioptres is given by:
A negative power of a lens indicates a:
When a lens is placed in a liquid, light refracts at:
For a lens immersed in a medium of refractive index \[n_1\], the power is related to the focal length by:
A concave lens has:
