Here’s How to Define Focal Length? CBSE Physics Question

CBSE Physics Question

BY Team Aakash Byju's

Light of shorter wavelength travels in a straight line. Light exhibits the phenomenon of reflection, refraction, dispersion and scattering.

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Optical instrument work on the principle of refraction of light.

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Lens is a refracting surface which refracts light focussed on it.

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FOCAL LENGTH OF THE LENS: It is a measure of convergence or divergence of light rays by an optical system.

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The distance between the pole and focus of the lens. Focal length of the lens depends upon the radius of curvature. f = R/2.

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Focal length of the plane surface is infinite.

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Focal length of concave lens is negative.

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Focal length of the convex lens is positive.

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The pole is the center of the spherical lens.

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Focal length of the lens is the optical power of the lens.

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