A concave lens is kept in contact with a convex lens of focal length `20 cm`. The combination works as a converging lens of focal length `100 cm`. Cal

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A concave lens is kept in contact with a convex lens of focal length `20 cm`. The combination ... length `100 cm`. Calculate power of concave lens.

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Description : 10. An object 5 cm in length is held 25 cm away from a converging lens of focal length 10 cm. Draw the ray diagram and find the position, size and the nature of the image formed. -Physics-10

Last Answer : Height of the Object, h0 = 5 cm Distance of the object from converging lens, u = -25 cm Focal length of a converging lens, f = 10 cm Using lens formula, Thus, the image is inverted and formed at a distance of 16.7 cm behind the lens and measures 3.3 cm. The ray diagram is shown below.

Description : A converging lens forms a three times magnified image of an object, which can be take on a screen. If the focal length of the lens is 30 cm, then the distance of the object from the lens is (a) - 55 cm (b) - 50 cm (c) - 45 cm (d) - 40 cm

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Last Answer : A. concave lens (Answer)

Description : 1. A concave lens has focal length of 20 cm. At what distance from the lens a 5 cm tall object be placed so that it forms an image at 15 cm from the lens? Also calculate the size of the image formed. [Delhi] -Chemistry-10

Last Answer : Answer. hope this helps youu

Description : A concave lens has focal length of 20 cm. At what distance from the lens a 5 cm tall object be placed so that it forms an image at 15 cm from the lens? Also calculate the size of the image formed. -Physics

Last Answer : Answer. I hope it helped you.

Description : 2. An object 50 cm tall is placed on the principal axis of a convex lens. Its 20 cm tall image is formed on the screen placed at a distance of 10 cm from the lens. Calculate the focal length of the lens. [All India] -Chemistry-10

Last Answer : this is the answer for the respected question

Description : A convex lens has a focal length of 10 cm. At what distance from the lens should the object be placed so that it forms a real and inverted image 20 cm away from the lens? What would be the size of ... ? With the help of a ray diagram show the formation of the image by the lens in this case. -Physics

Last Answer : This is the Answe:

Description : An object 50 cm tall is placed on the principal axis of a convex lens. Its 20 cm tall image is formed on the screen placed at a distance of 10 cm from the lens. Calculate the focal length of the lens. -Physics

Last Answer : The focal length' of convex length is 7.14 cm. Solution: The given quantities are Height of the object h = 50 cm Height of the image formed h' = -20 cm Image distance v = 10 cm The image ... object distance will be So the focal length will be Thus the focal length of the convex lens is 7.14 cm

Description : What is the power of a convex lens with a focal length of 20 cm ?

Last Answer : 20cm = 0.2 m We know , power p = 1 / f = 1 / 0.2 = + 5 D

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Last Answer : A double convex lens has radii 20 cm. The index of refraction of glass is 1.5. Compute ... immersed in carbon disulphide of refractive index 1.63.

Description : The power of a convex lens is +2.5. Then its focal length is (a) 20 cm (b) 50 cm (c) 30 cm (d) 40 cm

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Description : An object is placed on the principal axis of a convex lens of focal length 10 cm. If the distance of the object from the lens is 30 cm, what is the distance of the image formed? (1) 20 cm (2) 15 cm (3) 30 cm (4) 10 cm

Last Answer : (2) 15 cm

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Last Answer : (D) All the above 

Description : An object is located 1 meter in front of a converging lens having a focal length of 20 centimeters. At what distance behind the lens (whose thickness is negligible) will the image be formed? w) 18 centimeters x) 20 centimeters y) 22 centimeters z) 25 centimeters

Last Answer : ANSWER: Z -- 25 CENTIMETERS

Description : 11. A concave lens of focal length 15 cm forms an image 10 cm from the lens. How far is the object placed from the lens? Draw the ray diagram. -Physics-10

Last Answer : Focal length of concave lens (OF1), f = – 15 cm Image distance, v= – 10 cm According to the lens formula, The negative value of u indicates that the object is placed 30 cm in front of the lens. This is shown in the following ray diagram.

Description : A concave lens focal length 10 cm is placed on the axis of concave mirror of 10 cm radius at a distance of 5 cm from the mirror. An object is placed s

Last Answer : A concave lens focal length 10 cm is placed on the axis of concave mirror of 10 cm radius ... the object itself. Determine the position of the object.

Description : The two surfaces of a double concave lens are of curvature 10 cm and 40 cm. Find the focal length of the lens in water. The refractive index of water

Last Answer : The two surfaces of a double concave lens are of curvature 10 cm and 40 cm. Find the focal length of ... and that of the lens of the material is 3/2.

Description : 15. An object 2 cm high is placed at a distance of 64 cm from a white screen. On placing a convex lens at a distance of 32 cm from the object it is found that a distinct image of the object is formed on the screen. What is the focal length of the conve -Chemistry-10

Last Answer : Since, object-screen distance is double of object-lens separation, the object is at a distance of 2f from the lens and the image should be of the same size of the object.

Description : An object 2 cm high is placed at a distance of 64 cm from a white screen. On placing a convex lens at a distance of 32 cm from the object it is found that a distinct image of the object ... diagram to show the formation of the image in this position of the object with respect to the lens. -Physics

Last Answer : Since, object-screen distance is double of object-lens separation, the object is at a distance of 2f from the lens and the image should be of the same size of the object.

Description : The focal length of a convex lens is 50 cm. what is its power? -Do You Know?

Last Answer : convex ( so focal length is positive ) given : f = 50cm or +50×10^-2m so find p =? formula p =1/f p = 1/50×10^-2 p= 100/50 P = 2

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Description : A convex lens of focal length 30 cm is placed between a screen and a square plate of area `4cm^(2)`. The image of the plate formed on the screen is `1

Last Answer : A convex lens of focal length 30 cm is placed between a screen and a square plate of area ... Calculate the distance between the plate and the screen.

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Last Answer : The focal length of a convex lens of glass `(mu = 1.5)` in air is 30 cm. Find its focal length when the lens is placed in water `(mu = 4//3)`.

Description : A plano-convex lens `(mu = 1.5)` has a curved surface of radiys 15 cm. what is its focal length ?

Last Answer : A plano-convex lens `(mu = 1.5)` has a curved surface of radiys 15 cm. what is its focal length ?

Description : The radii of curvature of a double convex lens are 30 cm and 60 cm and its refractive index is 1.5. calculate its focal length.

Last Answer : The radii of curvature of a double convex lens are 30 cm and 60 cm and its refractive index is 1.5. calculate its focal length.

Description : The focal length of a convex lens is 50 cm. what is its power?

Last Answer : +2 D

Description : A student focuses the image of a candle flame, placed at about 2 m from a convex lens of focal length 10 cm, on a screen. After that he moves gradually the flame towards the lens and each time focuses its ... d) What is seen on the screen when the flame is very close (at about 5 cm) to the lens?

Last Answer : (a) The student moves the lens away from the screen to focus the image because on moving the candle towards the lens, the image distance increases. (b)The size of the image increases when the object ... on the screen. A virtual image is formed behind the candle on the same side of the screen.

Description : 1. The focal length of a convex lens is 50 cm. what is its power? 2. Among the Indian languages, which one is spoken maximum in the world after Hindi? 3. Which formulates fiscal policy? 4. ... Sun (in million kms.)? 20. Upanishads, also known as the Vedantas, are How many are these upanishads?

Last Answer : Answer : 1. +2 D 2. Bengali 3. Finance Ministry 4. China-Pakistan5. Lord Ellenborough 6. Leaf 7. Advocate General 8. Lithium and osmium 9. Chenab 10. Indigo 11. Canada 12. The Mellanesia 13. Leaf 14. Black 15. Atharvaveda 16. President 17. Roentgens 18. Third Plan 19. 149 20. 108

Description : A sphere of 1 cm radius is placed at the distance of 50 cm from the convex lens of 10 cn focal length. What would be the height of the image of sphere ?

Last Answer : 0.5cm

Description : 17. A doctor has prescribed a corrective lens of power +1.5 D. Find the focal length of the lens. Is the prescribed lens diverging or converging? -Physics-10

Last Answer : Power of lens (P) = 1/f P = 1.5D f = 1/1.5 = 10/15 = 0.66 m A convex lens has a positive focal length. Therefore, it is a convex lens or a converging lens.

Description : Where should an object be placed from a converging lens of focal length 10 c, so as to obtain a virtual image of magnification 2 ?

Last Answer : Where should an object be placed from a converging lens of focal length 10 c, so as to obtain a virtual image of magnification 2 ?

Description : A converging thin lens has a focal length of 27 centimeters. An object is placed 9 centimeters from the lens. Is the image of the object real or virtual?  

Last Answer : ANSWER: VIRTUAL

Description : A converging thin lens has a focal length of 27 centimeters. An object is placed 9 centimeters from the lens. Where is the image of this object formed?

Last Answer : ANSWER: -13.5 CENTIMETERS or 13.5 CENTIMETERS ON THE OBJECT SIDE OF THE LENS

Description : Pick up the correct statement from the following:  (A) The power of a lens is the reciprocal of its focal length  (B) The unit of power of the lens is Diopter  (C) The power of two or more thin lenses in contact is the power of the combination of the  lenses  (D) All the above 

Last Answer : (D) All the above 

Description : Pick up the correct statement from the following: (A) Spherical aberration may be reduced by diminishing the aperture (B) Spherical aberration may be minimised by replacing the single lens by a ... telescope objectives, a combination of convex lens and concave lens is used (D) All the above

Last Answer : (D) All the above

Description : At what distance should an object be placed from a convex lens of focal langth `15 cm` to obtain an image three times the size of the object ?

Last Answer : At what distance should an object be placed from a convex lens of focal langth `15 cm` to obtain an image three times the size of the object ?

Description : Find the position of an object which when placed in front of a concave mirror of focal length 20 cm, produces a virtual image which is twice the size

Last Answer : Find the position of an object which when placed in front of a concave mirror of focal length 20 cm ... image which is twice the size of the object.

Description : Ray coming from an object situated at infinity, fall on a convex lens and an image is formed at a distance of 16 cm from the lens. When a concave lens

Last Answer : Ray coming from an object situated at infinity, fall on a convex lens and an image is formed ... . Calculate the focal length of the concave lens.

Description : 3. Find the power of a concave lens of focal length 2 m. -Physics-10

Last Answer : Focal length of concave lens (f) = 2 m Power of lens (P) = 1/f = 1/ (-2) = -0.5D

Description : The focal length of a double convex lens is equal to radius of curvature of either surface. The refractive index of its material is

Last Answer : The focal length of a double convex lens is equal to radius of curvature of either surface. The refractive index of its material is

Description : An object is placed at `0.06` m from a convex lens of focal length `0.1`m. Calculate the position of the image?

Last Answer : An object is placed at `0.06` m from a convex lens of focal length `0.1`m. Calculate the position of the image?