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## What is the power of convex lens of focal length 50?

= 100/50 = **2 dioptre**. The SI unit of power is dioptre.

## What will be the focal length of a lens whose power is given as 5.0 D?

Answer: Focal length is inverse of power of lense…. F= 1/ P . so focal lenght of lens of power +2D is **0.5 m**.

## When the power of a lens is what is its focal length?

The power of a lens is defined as **reciprocal of the focal length of the lens**. A lens of small focal length has a large power of converging or diverging a parallel beam of light. The power of the lens is 1 diopter if its focal length is 1 m.

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

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. Answer: Since, **Power P = -2 D**, Focal length f = 100/(-2) = – 50 cm.

## What is the focal length of a lens of power 2.0 D?

Focal length of the lens is **-50cm** or 0.5m.

## Which lens is used if its d value is negative?

The focal length of a convex lens is positive and that of a **concave lens** is negative.

## What is the SI unit of focal length?

The SI unit of focal length is ‘**metre**‘.

## What is the relation between focal length and power?

The optical power of a lens is equal to the reciprocal of the focal length of the lens. **P = 1/f**. SI unit of power is dioptre (D) and that of focal length is metre (m).

## What is 2D power of lens?

Power of a lens is the reciprocal of its focal length in metres. If the power of a lens is -2D, it means that **1/f(in m) = -2D**. FYI, Since the focal length will be negative, this will be a concave lens. e3radg8 and 18 more users found this answer helpful.

## What is nature of lens if power of lens is 2.0 D?

Hence, it is a **concave lens**.

## What is the focal length of concave mirror?

Focal Length – **The distance between the pole P of the concave mirror and the focus F** is the focal length of the concave mirror. Thus, the focal length of a concave mirror can be estimated by obtaining a ‘Real image’ of a distant object at its focus, as shown in the figure.