The distance between an object and a screen is 100cm. A lens produces an image on the screen when the lens is placed at either of the positions 40cm apart. The power of the lens is nearly

 The central part of a convex lens is thicker than the edges. Because of its converging nature, this lens is called a converging lens. When light enters the lens, it undergoes refraction and eventually converges at a point known as the main focus, or F. The focal length is the distance between the primary focus and the lens’s centre. The power of the length is the reciprocal of the focal length. It is measured in diopters. The displacement technique of length is used to determine the focal length and power of a thin convex lens.

Place the convex lens in front of an object and record the distance at which the image formed. Let’s preserve the item and the screen in their current positions. Now slowly move the lens nearer the screen until the thing is clearly visible. After that, the image begins to fade. At that time, secure the lens. This is based on a simple idea. Even if we swap the object’s distance from the lens with the image’s distance from the lens, we’ll still obtain an image. The displacement length is then calculated as the distance between the first and second positions of the lens.

f = D2−d2/4D

f = 12−(0.4)/4×1

f = 1−0.16/4

f =.84/4

f = 0.21 m

Therefore, the power is given as P = 1/f …………….(2)

Substituting the value of f in equation (2)

P = 1/.21

P = 4.761diopter


Getting Info...
Cookie Consent
We serve cookies on this site to analyze traffic, remember your preferences, and optimize your experience.
It seems there is something wrong with your internet connection. Please connect to the internet and start browsing again.
AdBlock Detected!
We have detected that you are using adblocking plugin in your browser.
The revenue we earn by the advertisements is used to manage this website, we request you to whitelist our website in your adblocking plugin.
Site is Blocked
Sorry! This site is not available in your country.