Question

define the power of lens. the power of lens is +2.0D. find the focal length of the lens, explain with the help of figure whether this lens would converge or diverge a beam of light

Answer 1

hope this will help you

Answer 2

Answer:

The focal length of the lens = 0.5 m

Explanation:

The capability of lens to bend the light is termed as the power of lens. Also the greater the power the greater the refraction of light.

The power of a lens is also defined as the inverse of the focal length.

Mathematically,

$Power\ of\ a\ lens\ = \frac{1}{f}$

Where,

f = focal length of the lens which is measured in meters.

Power of a lens is measured in Dioptres (D).

Now from the question,

Power of the lens = +2 D

∴ $Power\ of\ a\ lens\ = \frac{1}{f}$

$2 = \frac{1}{f}$

⇒ f = 0.5 m

Hence, the focal length of the lens = 0.5 m