Two thin lenses of focal lengths 20 cm a...

Two thin lenses of focal lengths 20 cm and 25 cm are placed in contact. The effective power of the combinations is

Text Solution

Verified by Experts

Topper's Solved these Questions

QUESTION PAPER 2010
WB JEE PREVIOUS YEAR PAPER|Exercise PHYSICS|45 Videos
QUESTION PAPER 2012
WB JEE PREVIOUS YEAR PAPER|Exercise Subject: Physics|38 Videos

Similar Questions

Explore conceptually related problems

Two convex lenses of focal lengths f_1 and f_2 respectively are placed in contact each other. Then what will be power of their equivalent lens?

Two convex lenses of focal lengths f_(1) and f_(2) respectively are placed in contact with each other. Then what will be power of their equivalent lens?

Thin converging lenses of focal lengths 2 cm and 10 cm are used respectively as the objective and the eyepiece of a microscope. The distance between the optical centre of the lenses is 26 cm . If an object is placed at a distance of 2.25 cm from the objective , find the position and magnification of the final image.

Two lenses of focal lengths 6cm and 50 cm are used in construction of a telescope. Which lens will be used as an objective and why?

A convex lens of focal length 80 cm and a concave lens of focal length 50cm are placed in contact. The resulting will be—

Two identical equiconvex lenses, each of focal length f, are placed side by side in contact with each other with a layer of water in between them as shown in the figure. If refractive index of the material of the lenses is greater than that of water, how the combined focal length F is related to f?

Two lenses having power +15 m ^(-1) and +5 m^(-1) are placed in contact with each other in an ordinary microscope. If the image is formed at a distance of 25 cm , what is the magnifying power of the instrument ?

Two convex lenses of focal length 1.5 cm and 9 cm are arranged to form a microscope . A small object is placed 1.8 cm from the objective. If the image appears to be 37.5 cm from the eyepiece, what will be the distance between the objective and the eyepiece ?

WB JEE PREVIOUS YEAR PAPER-QUESTION PAPER 2011-PHYSICS

Which type of Gate the following truth table represents ?
Text Solution
|
A material has Poisson 's ratio 0.50 . If a uniform rod it suffers a l...
Text Solution
|
Two identical springs are connected to mass m as shown (k= spring con...
Text Solution
|
An object weighs m1 in a liquid of density d1 and that in liquid of ...
Text Solution
|
A body floats in water with 40% of its volume outside water. When the ...
Text Solution
|
Two soap bubbles of radii x and y coalesce to constitute a bubble of r...
Text Solution
|
A particle of mass m is located in a one dimensional potential field w...
Text Solution
|
In Young's double Slit experiment the two slits are d distances apar...
Text Solution
|
A plane progressive wave is given by y = 2 cos 6.284 (330 t-x) . ...
Text Solution
|
The displacement of a particle in S.H.M. varies according to the relat...
Text Solution
|
Two temperature scale A and B are related by (A- 42)/( 110 ) =(B-72)...
Text Solution
|
An ideal gas is compressed isothermally unit its pressure is doubled...
Text Solution
|
Air inside a closed container is saturated with water vapour . The ai...
Text Solution
|
1.56 xx 10 ^(5) J of heat is conducted through a 2 m^(2) wall of ...
Text Solution
|
A diver , at a depth of 12m in water ( mu = (4)/(3)) sees the sky ...
Text Solution
|
Two thin lenses of focal lengths 20 cm and 25 cm are placed in contact...
Text Solution
|
A convex lens of focal lengths 30 cm produces 5 times magnified real ...
Text Solution
|
If the focal length of the eye piece of a telescope is doubled, its ma...
Text Solution
|
A plano -concave lens is made of glass of refractive index 1.5 and rad...
Text Solution
|
Four charges equal to -Q are placed at the four corners of a square an...
Text Solution
|