A convex lens makes a real image 4 cm lo...

A convex lens makes a real image 4 cm long on a screen. When the lens is shifted to a new position without disturbing the object, we again get a real image on the screen which is 16 cm tall. The length of the object must be

`1/4cm`

`8cm`

`12cm`

`20cm`

Text Solution

Verified by Experts

(b) `0=sqrt(l_(1)l_(2))=sqrt(4xx16)=8cm`

Topper's Solved these Questions

QUESTION-PAPERS-2018
BITSAT GUIDE|Exercise PHYSICS|40 Videos
SEMICONDUCTOR DEVICES AND LOGIC GATES
BITSAT GUIDE|Exercise BITSAT Archives|5 Videos

Similar Questions

Explore conceptually related problems

A convex lens forms a real image 16 mm long on a screen. If the lens is shifted to a new position without disturbing the object or the screen then again a real image of length 81 mm is formed. The length of the object must be

In displacement method, the lengths of images in the two positions of the lens betwent the object and the screen are 9 cm and 4 cm respectively. The length of the object must be

A convex lens forms an image of an object on a screen 30 cm from the lens. When the lens is moved 90 cm towards the object, then the image is again formed on the screen. Then, the focal length of the lens is

A convex lens produces an image of a real object on a screen with a magnification of 1/2. When the lens is moved 30 cm away from the object, the magnification of the image on the screen is 2. The focal length of the lens is

A convex lens forms a real image on a screen placed at a distance 60 cm from the object. When the lens is shifted towards the screen by 20 cm , another image of the object is formed on the screen. The focal length of the lens is :

A real image is formed by a convex lens. If we put a concave lens in contact with it, the combination again forms a real image. The new image

A lens placed between a candle and a fixed screen forms a real triply magnified image of the candle on the screen. When the lens is moved away form the candle by 0.8m without changing the position of the candle, a real image one-third the size of the candle is formed on the screen. Determine the focal length of the lens.

A convex lens forms an image of an object on a screen. The height of the image is 9 cm . The lens is now displaced until an image is again obtained on the screen. Then height of this image is 4 cm . The distance between the object and the screen is 90 cm.

BITSAT GUIDE-RAY OPTICS-All Questions

An object appraches a convergent lens from the left of the lens with a...
Text Solution
|
A concave lens and a convex lens have same focal length of 20 cm and b...
Text Solution
|
A source of light lies on the angle bisector of two plane mirrors incl...
Text Solution
|
On the axis of a spherical mirror of focal length f a short linear obj...
Text Solution
|
The speed at which the image of the luminous point object is moving, i...
Text Solution
|
A thin convergent glass lens (mug=1.5) has a power of +5.0D. When this...
Text Solution
|
The reflective surface is given by y=2 sinx. The reflective surface is...
Text Solution
|
With a concave mirror, an object is placed at a distance x(1) from the...
Text Solution
|
An electromagnetic radiation of frequency v, wavelength lamda, travell...
Text Solution
|
When a glass slab is placed on a cross made on a sheet, the cross appe...
Text Solution
|
A layered lens is made of materials indicated by shades in the figure....
Text Solution
|
Resolving power of a telescope will be more, fi the diameter (a) of th...
Text Solution
|
A point object is placed at the focus of the bio-conved lens. What sho...
Text Solution
|
A ray of light is incident on the interface between water and glass at...
Text Solution
|
In the Young's double slit experiment , a mica slip of thickness t and...
Text Solution
|
A film projector magnifies a 100cm^(2) film strip on a screen. If the ...
Text Solution
|
A convex lens makes a real image 4 cm long on a screen. When the lens ...
Text Solution
|
The maximum value of index of refraction of a material of a prism whic...
Text Solution
|
The focal lengths of objective and the eyepiece of a compound microsco...
Text Solution
|
Which of the following is a wrong statement?
Text Solution
|