# What is the power of convex lens if the focal length is 20 cm?

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## What is the power of a convex lens if its focal length is 20cm?

p = 1/f=1/20=100/20=5 diopter.

## What is the focal length of 20cm?

A concave lens has a focal length of 20 cm.

## What is the power of a convex lens of focal length?

The power of a lens is defined as the reciprocal of the focal length. Lens power is measured in dioptres (D). Converging (convex ) lenses have positive focal lengths, so they also have positive power values. Diverging (concave ) lenses have negative focal lengths, so they also have negative power values.

## What will be the power of convex lens of focal length 25 cm?

In this question it is given that the lens is convex, and its focal length is 25 cm. First we will convert the focal length in meters. … Thus, the power of the lens is +4D.

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## What is the power of lens if its focal length is 50 cm?

= 100/50 = 2 dioptre.

## What is the power of a lens having focal length cm?

Explanation: Power = 1/f(m) Power is the reciprocal of focal length in meters.

## What is the power of a convex lens of focal length 40 cm?

So, Power of convex lens is + 2.5 D.

## What is the focal length of a lens of power 8d?

As the power of a lens is reciprocal of the focal length, the convex lenses have positive power. Therefore, the correct answer is A. Note: We can find the focal length of this lens in m by doing a reciprocal of power which will give us focal length as 0.125 m or 12.5 cm.

## What is the power of a lens with a focal length of 10 cm?

Thus, the powerof this convex lens is +10 dioptres which is also written as +10D.

p = 10 D.

## Is power of convex lens positive?

Additional Information: Power of convex lens is positive as it converges the light rays incident on it. Convex lens is also referred to as a converging lens.

## What is the power of a convex lens of focal length 0.5 meters?

Thus, a diverging lens having a focal length of 1 m has a power of -1 diopter, and a converging lens of focal length 0.5 m has a power of two diopters.

## Is the power of a lens is 2D What is the focal length?

Answer: Power of a lens is -2D, negative sign indicates it is a Concave lens. Focal length (in meters)=1/power of the lens, thus focal length=1/2=0.5m=50cm.

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## What is the power of the focal length?

The power of a lens is defined as the reciprocal of its focal length in meters, or D = 1/f, where D is the power in diopters and f is the focal length in meters.