Sumati did some preliminary experiment with the lenses and found out that the
magnification of the eyepiece (L 2 ) is 3. If in her experiment with L 2 she found an image at 24
cm from the lens, at what distance did she put the object?
(a) 72 cm
(b) 12 cm
(c) 8 cm
(d) 6 cm

1 Answer

Answer :

(c) 8 cm

Related questions

Description : What is the power of the objective lens of a microscope if an eyepiece of power 10x is used and the total magnification of the object is 40x? (A) 4 (B) 10 (C) 40 (D) 400

Last Answer : (A) 4

Description : Pick up the correct specification of Ramsden eyepiece from the following:  (A) It consists of two equal piano convex lenses  (B) The curved surfaces of Plano-convex lenses face each other  (C) ... from a point on the diaphragm enter the eye as a  parallel beam  (D) All the above 

Last Answer : (D) All the above 

Description : Where should an object be placed from a converging lens of focal length 20 cm, so as to obtain a real image of magnification 2?

Last Answer : Where should an object be placed from a converging lens of focal length 20 cm, so as to obtain a real image of magnification 2?

Description : If a light microscope has an eyepiece lens of magnification x15 what magnification of objective lens would be needed to get a total magnification of x1500?

Last Answer : The total magnification is equal to the magnification of theeyepiece multiplied by the magnification of the objective lens.So in this case the objective lens would need to be 100X.

Description : How do you find the total magnification of the eyepiece and the objective lens?

Last Answer : Need answer

Description : What is a compound microscope? (1) A microscope that has one lens. (2) A microscope that has two sets of lenses : an occular lens and an eyepiece. (3) A microscope whose lenses are concave. (4) A microscope whose lenses are convex.

Last Answer : (2) A microscope that has two sets of lenses : an occular lens and an eyepiece. Explanation: A compound microscope is a microscope which uses multiple lenses to collect light from the ... lens provides the primary magnification which is compounded (multiplied) by the ocular lens (eyepiece).

Description : What is a compound microscope? (1) A microscope that has one lens. (2) A microscope that has two sets of lenses : an occular lens and an eyepiece. (3) A microscope whose lenses are concave. (4) A microscope whose lenses are convex.

Last Answer : A microscope that has two sets of lenses : an occular lens and an eyepiece.

Description : A compound lens is made of two lenses having powers `+15.5 D` and `-5.5D`. An object of 3cm height is placed at a distance of 30 cm from this compound

Last Answer : A compound lens is made of two lenses having powers `+15.5 D` and `-5.5D`. An object of ... cm from this compound lens. Find the size of the image.

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 : 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 : Based on the diagram shown, what kind of lenses would Sumati need to make the telescope? (a) Concave lenses (b) Convex lenses (c) Bifocal lenses

Last Answer : (b) Convex lenses

Description : An object is placed at a distance of `1.5 m` from a screen and a convex lens is interposed between them. The magnification produced is `4`. What is th

Last Answer : An object is placed at a distance of `1.5 m` from a screen and a convex lens is interposed between ... `4`. What is the focal length of the lens ?

Description : In the following diagram are shown the position of an object O, image I and two lenses. The focal length of one lens is also given. Determine the foca

Last Answer : In the following diagram are shown the position of an object O, image I and two lenses. The ... given. Determine the focal length of the other lens.

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

Last Answer : (d) - 40 cm

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 : 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 : 2. A convex lens forms a real and inverted image of a needle at a distance of 50 cm from it. Where is the needle placed in front of the convex lens if the image is equal to the size of the object? -Physics-10

Last Answer : The position of the image should be at 2F since the image is the real and same size. It is given that the image of the needle is formed at a distance of 50 cm from the convex lens. Therefore, the needle is ... (u) = - 50 cm Image distance, (v) = 50 cm Focal length = f According to the lens formula,

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 : 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 : 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 : A convex lens is placed on an optical bench and is moved till it gives a real image of an object at a minimum distance of 80 cm from the latter. Find

Last Answer : A convex lens is placed on an optical bench and is moved till it gives a real image of an object ... cm from the lens, find the position of the image.

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 : 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

Description : The measured distance from a lens to the object is 20 cm and from the lens to the image is 5 cm. Calculate the focal length

Last Answer : 1/4

Description : In a telescope the object glass of focal length 14 cm, is located at 20 cm from the diaphragm. The focussing lens is midway between them when a staff 16.50 m away is focussed. The focal length of the focussing lens, is (A) 5.24 cm (B) 6.24 cm (C) 7.24 cm (D) 8.24 cm

Last Answer : (C) 7.24 cm

Description : When an object is placed at a distance of `60 cm` from a convex spherical mirror, the magnification produced is `1//2`. Where should the object be pla

Last Answer : When an object is placed at a distance of `60 cm` from a convex spherical mirror, the magnification ... placed to get a magnification of `1//3` ?

Description : An object is placed in front of a concave mirror of radius of curvature `40 cm` at a distance of `10 cm`. Find the position, nature and magnification

Last Answer : An object is placed in front of a concave mirror of radius of curvature `40 cm` at a ... Find the position, nature and magnification of the image.

Description : Pick up the correct statement from the following: (A) If the image of the object does not fall on the plane of the cross-lines, parallax exists (B) Parallax has nothing to do with the eyepiece (C) The eyepiece is adjusted for clear vision of the cross hairs (D) All the above

Last Answer : (D) All the above

Description : At what distance must an object be placed from mirror in order that a real image double its size may be obtained? (a) -24 cm (b) 32 cm (c) -40 cm (d) 45 cm

Last Answer : (a) -24 cm

Description : A ball moving with uniform velocity comes to rest in a distance of 72 m in 6 s. Its initial velocity and retardation are (a) 12 m/s and 2 m/s2 (b) 12 m/s and 4 m/s2 (c) 24 m/s and 8 m/s2 (d) 24 m/s and 4 m/s2

Last Answer : Ans:(d)

Description : An object is placed at a distance of 12 cm in front of a concave mirror of radius of curvature 30 cm. List four characteristics of the image formed by the mirror. -Science

Last Answer : Here, radius of curvature of concave mirror, R = 30 cm. Therefore, focal length of the mirror, f = R/2 = 30/2 = 15 cm Also, object distance, u = 12 cm Hence, knowing the focal length of mirror and ... (i) Erect (ii) Larger in size than that of the object (iii) Virtual and (iv) Behind the mirror.

Description : 12. An object is placed at a distance of 10 cm from a convex mirror of focal length 15 cm. Find the position and nature of the image. -Physics-10

Last Answer : Focal length of convex mirror (f) = +15 cm Object distance (u) = - 10 cm According to the mirror formula, The image is located at a distance of 6 cm from the mirror on the other ... and a value of less than 1 of magnification indicates that the image formed is virtual and erect and diminished.

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 : 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 : An object is 60 cm in front of a thin lens, the image being 300 cm on the other side of the lens. Calculate the displacement of the image, when the ob

Last Answer : An object is 60 cm in front of a thin lens, the image being 300 cm on the other side of the ... when the object is moves 20 cm nearer to the lens.

Description : A positive lens with a focal length of 10 cm forms a real image of an object 20 am away from the lens. How far is the real image from the lens? a. 5 cm b. 10 cm c. 15 cm d. 20 cm

Last Answer : d. 20 cm

Description : A positive lens with a focal length of 10 cm forms a real image of an object 20 am away from the lens. How far is the real image from the lens? ∙ a. 5 cm ∙ b. 10 cm ∙ c. 15 cm ∙ d. 20 cm

Last Answer : ∙ d. 20 cm

Description : In Newton's ring experiment, the diameter of the 15 th ring was found to be 0.590 and that of the 5 th ring was 0.336 cm. If the radius of Plano convex lens is 100 cm, compute the wavelength of light used. A. 5885 A 0 B. 5880 A o C. 5890 A o D.5850 A

Last Answer : B. 5880 A o

Description : The ratio of the angles subtended at the eye, by the virtual image and the object, is known as telescopes (A) Resolving power (B) Brightness (C) Field of view (D) Magnification

Last Answer : (D) Magnification

Description : A what distance must an object be placed from convex lens of power 4D to obtain a real image three times the size of the object ?

Last Answer : A what distance must an object be placed from convex lens of power 4D to obtain a real image three times the size of the object ?

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 : Pick up the correct statement from the following: (A) A refracting telescope consists optically of two lenses (B) The principal axes of both the lenses coincide the optical axis of the telescope (C) The lens nearer the object to be viewed is convex and is called objective (D) All the above

Last Answer : (D) All the above

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 : Pick up the correct statement from the following: (A) The diaphragm is placed between eyepiece and the objective but nearer to the former (B) The diaphragm is placed between the eyepiece and objective ... outer component of the objective is a double-convex lens of crown glass (D) All the above

Last Answer : (D) All the above

Description : Which one of the following statements is not correc t? (a) Parallax error is eliminated when there is no change in the staff reading when eye is moved up and down (b) The objective lens is ... (d) The eyepiece need not be adjusted after the first set up when the same surveyor is taking readings

Last Answer : (b) The objective lens is to be focused towards a white or bright background for clear visibility of cross-hairs

Description : Two concave lenses of 60 cm focal length are cemented on either side of a convex lens of 15 cm  focal length. The focal length of the combination is  (A) 10 cm  (B) 20 cm  (C) 30 cm  (D) 40 cm 

Last Answer : (C) 30 cm 

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.