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## How to find out the radius of curvature of a covex lens when focal length is given?

Asked by 12th March 2008 9:13 PM

## Q.On a convex lens ,light of red and violet colour is incident separately , then how does the focal length of lens change?

Asked by Ravi consul 4th March 2015 6:48 PM

## the distance between a convex lens and a plane mirror is 10 cm.The parallel rays incidenton the convex lens after reflection from the mirror form an image at the optical centre of the lens.Find the focal length of the lens

Asked by dev.sultanpur123 1st June 2015 12:52 AM

## I got to knew that when light passes through the optical centre, then it bent , but as the lens is very thin , this bent is negligible and thus we neglect it but when other rays passes through the lens(except optical centre) then why does they bent more?lens is thin so why should'nt we neglect it too??

Asked by jgprmr 17th June 2017 12:38 AM

## When light travels in direction of optical centre of convex lens , it suffers very very slight deviation .....so from this, is it correct to conclude that such light rays/waves which are trevelling in direction of optical centre are actually travelling along the normal?explain

Asked by jgprmr 17th June 2017 9:25 PM

## If the image formed in cinema is real then shouldn't it be inverted, and how do they avoid it?

Asked by nileshpatel19752000 13th October 2017 11:52 PM

## Give me crct solution with clear explanation

Asked by venkat 8th November 2017 6:26 PM

## A LUMINOUS OBJECT IS PLACED AT A DISTANCE OF 30CM FROM THE CONVEX LENS OF FOCAL LENGTH 20CM.ON THE OTHER SIDE OF THE LENS,AT WHAT DISTANCE FROM THE LENS A CONVEX MIRROR OF RADIUS OF CURVATURE 10CM BE PLACED IN ORDER TO HAVE AN UPRIGHT IMAGE OF THE OBJECT COINCIDENT WITH IT?A-12CM,B-30CM,C-50CM,D-70CM

Asked by Priyanka 13th November 2017 4:04 PM

## an object is placed at a distance of f/2 from a concavex lens. The image will be? A-at 3f/2,real and Inverted.B-at 2f virtual and erect. C-at f real and inverted. D-at one of the foci virtual and double size.

Asked by Priyanka 13th November 2017 9:35 PM

## A Plano convex lens of refractive index=1.5,silverd at the convex surface behave as an concave mirror of f=20cm.what is the radius of curvature of curved surface? Options are 40cm,20,60,30all in cm

Asked by Priyanka 13th November 2017 9:39 PM

## Astronomical telescope has two lens of focal power 0.5D,and 20D.its magnifying power is? 1-40cm,2-10cm,3-100cm,4-35cm

Asked by Priyanka 15th November 2017 9:16 AM

## A student performed an experiment with convex lens and found the virtual image of an object.  Find : (a) Position of the object.  (b) Draw ray diagram for the above situation.

Asked by pdcavita 11th December 2017 12:19 PM

## A student focuses the image of a well illuminated distant object on a screen using a convex lens. After that he gradually moves the object towards the lens and each time focuses its image on the screen by adjusting the lens.  a)  In which direction - towards the screen or away from the screen, does he move the lens?  b) What happens to the image on the screen when he moves the object very close to the lens?

Asked by pdcavita 19th December 2017 6:43 AM

## A student focuses the images of a well illuminated distant object on a screen using a convex lens. After that he gradually moves the object towards the lens and each time focuses its image on the screen by adjusting the lens.  (¡) what happens to the size of the image - does it decrease or increase?

Asked by pdcavita 20th December 2017 6:15 PM

## If a convex lens iis enlongated , then how the focal length and thickness will decrease or increse?what is curvature in lens here?

Asked by sucharitasahoo1 24th December 2017 12:52 AM

## A SCREEN IS PLACED 90 CM FROM AN OBEJCT. THE IMAGE OF THE OBJECT ON THE SCREEN IS FORMED BY A CONVEX LENS AT TWO DIFFERENT LOCATIONS SEPARATED BY 30 CM. FIND THE FOCAL LENGTH OF THE LENS.

Asked by sohamsouthpoint02 30th December 2017 1:28 AM

## a convex lens of focal length f is cut into two halves such that one surface of each is plane what is the focal length of each half

Asked by deepakphy93 3rd January 2018 1:08 PM

## Calculate the minimum dist. between object and its real image formed by convex lens of focal length F

Asked by gpnkumar0 5th January 2018 8:41 PM

## How to find the focal length of combination of lens

Asked by lovemaan5500 7th January 2018 6:58 AM

## Which type of lens is used in projector?

Asked by Somenathdewanji2050 29th January 2018 7:11 AM

## A biconvex lens made of  a transparent medium of n=1.5 is immetrsed in a medium of n=1.33.will the lens behave converging or diverging?give reason.

Asked by vasturushi 1st February 2018 9:46 PM

## A convex lens is placed in contact with a plane mirror. a point object is placed 20cm on the axis of the combination has its image coincideing with itself.what is the focal length of the lens?

Asked by vasturushi 1st February 2018 9:50 PM

## Can you give me the explanation

Asked by gpnkumar0 4th February 2018 9:34 PM

## pls solve it

Asked by gpnkumar0 4th February 2018 9:41 PM

## how can we identtify lens without touching it

Asked by janibirwa1 18th February 2018 12:00 PM

## A screen is placed at a distance of 100 cm from an object. The image of the object isformed on the screen by a convex lens for two different locations of the lens separated by 20 cm. Calculate the focal length of the lens used.

Asked by Raj 20th February 2018 5:54 AM

## Dera sir, please explain the displacement method to find the focal length of the convex lens in detail

Asked by modi72879 22nd February 2018 10:03 PM

## A point object O is kept at a distance of 30 cm of a convex lens power +4D towards its left.It is observed that when a convex mirror is kept on the right side at a distance of 50 cm of the convex lens ,the image of the object O formed by the lens mirror combination with the object itself.Calculate the focal length of the convex mirror.

Asked by Balbir 25th February 2018 11:32 AM

## PLS EXPLAIN

Asked by gpnkumar0 14th March 2018 9:17 PM

## plz solve the question with explanation

Asked by futureisbright051101 11th April 2018 6:48 AM

## Q. 3

Asked by Rayeesa 25th April 2018 9:55 PM

## Q. 4

Asked by Rayeesa 25th April 2018 9:57 PM

## Q. 5

Asked by Rayeesa 25th April 2018 9:59 PM

## Q. 6

Asked by Rayeesa 25th April 2018 10:00 PM

## A magnifying lens of focal length of 20 cm is held 10 cm away from the object 0.25 cm l9ng. Find the position, nature of the image, power and magnification of the lens.

Asked by lakhinandanbora21590 11th July 2018 11:35 PM

## A concave lens produces an image 20cm from the lens of an object placed 30cm form the lens calculate the power of the lens

Asked by Satish.ouc 15th July 2018 10:21 AM

## Q1:Where should an object be placed in front of a convex lens of focal length 0.12 m to obtain a real image of size three times the size of the of the object,on the screen? Q2:A convex lens forms an inverted image of size same as that of the object which is placed at a distance 60 cm in front of the lens.Find:a.The position of the image and b.The focal length of the lens. Q3:A concave lens forms an erect image of 1/3rd size of the object which is placed at a distance 30 cm in front of the lens.Find:a.The position of the image and b.The focal length of the lens.

Asked by kaursukhjindersukh 3rd September 2018 10:38 PM

## what this

Asked by krishdabhoya2003 22nd September 2018 7:50 PM

## 1. Why do light rays passing through optical centre of lens experiences no deviation?  2. Why it is harmful to look at the sun through convex lens?

Asked by agraharianiruddha 5th October 2018 6:14 PM

## how can we identify the lenses experimentally

Asked by abhishekayush15 11th November 2018 10:15 AM

## how can we find the focal length of a mirror or lenses

Asked by abhishekayush15 11th November 2018 10:17 AM

## electronic technician use .............. lens

Asked by rohitmotkar 27th November 2018 11:06 AM

## Distinguish between concave and convex lens

Asked by sangeeta735200 13th December 2018 7:52 PM

## An object placed on ameter scale at 8 cm mark was focused on a white screen placed at 92 cm mark,using a converginglens placed on the meter scale at 50 cm mark. a)  find the focal length of the converging lens b) find the position of the image formed if the object is shifted towards the lens at a position of 29 cm c) state the nature of image formed if the object is further shifte towards the lens.

Asked by rs1702 7th January 2019 12:09 PM