Why is the focal point for any convex lens a little inexact with ordinary white light?

Question

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Answer 1

The focal length of a convex lens is given by
$\frac{1}{f} = (\frac{n _{m a t e r i a l}}{n _{m e d i u m}} - 1) (\frac{2}{R})$
Since the refractive index of material is different for different colours, the focal length of the lens is different for them. Hence the constituents of white light bend by different amounts.

Answer 2

The focal length of a convex lens is given by

\frac{1}{f} = (\frac{n _{m a t e r i a l}}{n _{m e d i u m}} - 1) (\frac{2}{R})

Since the refractive index of material is different for different colours, the focal length of the lens is different for them. Hence the constituents of white light bend by different amounts.

Why is the focal point for any convex lens a little inexact with ordinary white light?

White light has a very long wavelength, compared to other colors.

White light has a very short wavelength, compared to other colors.

White light is made up of colors of light, which bend different amounts as they pass through the lens.

White light bends more than all the other colors.

White light bends less than all the other colors.

The focal length of a convex lens made of flint glass is $15 c m$ . To remove its chromatic aberration, it is placed in contact with a concave lens made of crown glass. Find the focal length of the concave lens. The ratio of dispersive powers of flint glass to crown glass is $1.5$ .

A narrow white light beam fails to converge at a point after going through a converging lens. This defect is known as :

When an extended white object is placed before a convex lens, colored images are formed. The image of the smallest size is of the color:

In chromatic aberration of a convex lens, :

Chromatic aberration(distance between the focal lengths for extreme wavelengths) of a convex lens can be reduced by(Assume lenses are kept in vacuum)

Revise with Concepts

Chromatic Aberration

Why is the focal point for any convex lens a little inexact with ordinary white light?

White light has a very long wavelength, compared to other colors.

White light has a very short wavelength, compared to other colors.

White light is made up of colors of light, which bend different amounts as they pass through the lens.

White light bends more than all the other colors.

White light bends less than all the other colors.

The focal length of a convex lens is given byf1​=(nmedium​nmaterial​​−1)(R2​)Since the refractive index of material is different for different colours, the focal length of the lens is different for them. Hence the constituents of white light bend by different amounts.

The focal length of a convex lens made of flint glass is 15cm. To remove its chromatic aberration, it is placed in contact with a concave lens made of crown glass. Find the focal length of the concave lens. The ratio of dispersive powers of flint glass to crown glass is 1.5.

A narrow white light beam fails to converge at a point after going through a converging lens. This defect is known as :

When an extended white object is placed before a convex lens, colored images are formed. The image of the smallest size is of the color:

In chromatic aberration of a convex lens, :

Chromatic aberration(distance between the focal lengths for extreme wavelengths) of a convex lens can be reduced by(Assume lenses are kept in vacuum)

Revise with Concepts

Chromatic Aberration

The focal length of a convex lens made of flint glass is $15 c m$ . To remove its chromatic aberration, it is placed in contact with a concave lens made of crown glass. Find the focal length of the concave lens. The ratio of dispersive powers of flint glass to crown glass is $1.5$ .