Question

write the definition of power of lens. give its si unit. name the instrument to measure the power of lens.​

Answer 1

$\huge\pink{Solution}$

Power of lens is defined as ability of a lens to converge / diverge a beam of light rays falling on lens . Power of lens is reciprocal of focal length where p is power of lens and f is focal length.

Dioptre is the SI unit for measuring power of a lens.

lensometer is the instrument to measure the power of lens.

Answer 2

Explanation:

Instrument that can directly measure the power of lens is called lensometer.

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