# What is the power of a concave lens of focal length 4 m?

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Answer: Power of a lens is equal to the reciprocal of its focal length. It is given by : So, the power of the lens is 0.25 D.

## What is power of a concave lens of focal length 4m?

So, the power of the lens is 0.25 D.

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

In the case of a concave lens, the power will always be negative as the focal length is negative.

## What is the power of a concave lens of focal length 2 m?

The focal length of the concave lens is always negative. Hence, the given focal length is -2m. Formula: Power = 1/focal length. Hence, Power is -0.5 dioptre.

## What is the power of concave lens of focal length 5 cm?

So, power of lens is -20 D.

## What is the power of concave lens of focal length 200?

Hence, The power of the concave lens is -0.5 D.

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

So, the power of a concave lens is (-5 D).

## What is the power of a concave lens whose focal length is 75?

POWER = 1/F (metres) » POWER = 100 / -75 = -(4/3) = 1.33 DIOPTRES.

## What is power of concave lens of focal length 50 cm?

Answer: The power of a lens is 1/focal length (measured in meters). So, 50 cm is 1/2 meter, so the power is -2; D stands for diopters, the unit of power for lenses. Hence, the power of a concave lens of focal length 50 cm is -2D.

## How do you find the power of a concave lens?

1. Given that, Focal length of the concave lens, f = 2 m.
2. To find, Power of the lens.
3. Solution, The relation between power and focal length of the lens is inverse. Power is given by : P = 1/f.
4. f is the focal length of the lens and it is negative for concave lens.

## What is the power of a concave lens whose focal length is cm75 0?

P = – 1.33 Diopter.

= -50 dioptres.

## What is the power of a concave lens of focal length 25 m?

f=-25cm As P=100f,f=100-25=-4dioptre.

## What is the power of lens of focal length 5cm?

The magnifying power of the convex lens is 6.

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## What is the magnification of convex lens of focal length 5 cm?

Correct answer:The magnification of the magnifying glass is (d) 5.

## What is the power of concave lens?

The power of the concave lens is negative. Concave lens surfaces have a virtual radius of curvature, and thus a negative curvature. Optical power is denoted by the same convention signs that are used for focal length.