Question

If the power of the lens is +4D.then the focal length of lens and nature of the len

Answer 1

Answer:

power of a lens is determined by the formula

p=1/f(when focal length is in metres) &

p=100/f(when focal length is in centimetres)

hair, the power is given as four diopters point on equity we get,

4=100/f

f=100/4

=25cms

Answer 2

The focal length of lens is +25 cm and the lens is convex lens.

Explanation:

Given power of lens P = +4D

The relation between power and focal length of lens is given by

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

Here, f is focal length of lens in meter(m).

Substitute the given values, we get

$+4D=\frac{1}{f}$

$f =\frac{1}{+4D} =0.25m$

$f=+25 cm$

As the focal length of lens is positive, so the lens is convex lens.

Thus, the focal length of lens is +25 cm and the lens is convex lens.

Topic : Power of lens.

Learn more:

https://brainly.in/question/13366245

https://brainly.in/question/2079718