What is the focal length of the combination when both lenses are in contact?

The focal length of the combination of two convex lenses in contact is f. and if they are separated by a distance, then focal length of the combination is f1. .

When two lenses are placed in contact the focal length of the combination is equal to the sum of the focal length of the lenses?

such a lens is called an equivalent lens and its focal length is called the equivalent focal length. Hence, when thin lenses are combined, the reciprocal of the ir effective focal length will be equal to the sum of the reciprocals of the individual focal lengths.

What is the power of combination of two lenses of focal length 10cm and?

So, the effective power of combination is 30 cm.

What is the power of a combination of lenses?

The power of combination of lenses would be the algebraic sum of the powers of the individual lenses.

What is combination of lens?

Combination of lenses. When two lenses are used in combination, the first one forms an image that then serves as the object for the second lens. The magnification of the combination is the ratio of the height of the final image to the height of the object. This is the final image produced by the combination of lenses.

When two lenses are placed in contact the focal length of the combination is equal to the sum of the focal lengths of the lenses True or false?

A Focal System When the distance of separation between the two lenses (d) is equal to the sum of the individual focal lengths (f1 + f2), the combined focal length is infinite.

How do you find the equivalent focal length of a combination?

$\mu $ is the refractive index of glass used. And, ${{R}_{1}}$ and ${{R}_{2}}$ are the radius of curvature of two sides of the lens. Hence, the equivalent focal length of the given lens combination is equal to $\dfrac{R}{{{\mu }_{1}}-{{\mu }_{2}}}$.

What is the power of convex lens of focal length 25 cm?

Answer: Power is expressed as the inverse of focal length, where a focal length of 1 meter is equal to one diopter. So a 25 cm. focal length (0.25 meters) has a power of 4 diopters.

What is the SI unit of power lens?

dioptre
Power of Lens and its Unit The S.I. unit of power is dioptre (D). Hence, one dioptre is the power of a lens of focal length one meter.

What is power of combination of lenses?

Thus the power of the combination of lenses is the algebraic sum of the powers of individual lenses. If two lenses are separated by a distance d metre, then the power of the combination of lenses is given by a relation.

What is the formula of combination of lenses?

If the lenses of focal lengths f1 and f2are “thin”, the combined focal length f of the lenses is given by 1f=1f1+1f2 1 f = 1 f 1 + 1 f 2 while if the lenses are separated by some distance d then the combined focal length is given by 1f=1f1+1f2−df1f2 1 f = 1 f 1 + 1 f 2 − d f 1 f 2 .