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 : 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
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 lens or combination of lenses in which the following defect is completely eliminated is called aplanatic (A) Spherical aberration (B) Chromatic aberration (C) Coma (D) Astigmatism
Last Answer : (A) Spherical aberration
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
Description : Cross hairs in surveying telescopes, are fitted (A) In the objective glass (B) At the centre of the telescope (C) At the optical centre of the eye piece (D) In front of the eye piece
Last Answer : (D) In front of the eye piece
Description : When you are focusing on a object in which order should the three objective lenses always be used?
Last Answer : Need answer
Description : The magnifying power of an astronomical telescope can be decreased by – (1) decreasing the focal length of the eyepiece (2) increasing the focal length of the eyepiece (3) increasing the focal length of the objective (4) None of these
Last Answer : (2) increasing the focal length of the eyepiece Explanation: The magnifying power (M) of astronomical is given by M = (focal length of objective)/(focal length of eye piece). This ... piece should be small. Similarly, for decreased magnification, focal length of eye piece should be increased.
Description : Pick up the correct statement from the following: (A) In astronomical telescope, the rays from the object after refraction at the objective are brought to a focus before entering the eyepiece to produce ... the objective traversing through the eyepiece, is called line of sight (D) All the above
Description : The magnifying power of an astronomical telescope can be decreased by (1) decreasing the focal length of the eyepiece (2) increasing the focal length of the eyepiece (3) increasing the focal length of the objective (4) None of these
Last Answer : increasing the focal length of the eyepiece
Description : Are Objective lenses standardized? [microscope]?
Last Answer : I have bought a number of used objectives on line, and have never had the problem of one not fitting, but that may have been luck.
Description : Based on the diagram shown, what kind of lens is used to make the overhead projector? (a) concave lenses (b) convex lenses (c) bifocal lenses (d) flat lenses
Last Answer : (b) convex lenses
Description : 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
Last Answer : (c) 8 cm
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 : 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 : 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 : Which one of the following lenses should be used to correct the defect of astigmatism? (1) Cylindrical lens (2) Concave lens (3) Convex lens (4) Bifocal lens
Last Answer : (1) Cylindrical lens Explanation: Astigmatism is an optical defect in which vision is blurred due to the inability of the optics of the eye to focus a point object into a sharp focused image ... lens, and cannot be corrected by standard spectacle lenses, but can be corrected by contact lenses.
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
Description : What is lens? Explain the difference between convex and concave lenses.
Last Answer : Lens: A lens is a piece of glass or other transparent material like plastic whose one or both side is spherical. Types There are two types of lenses. 1. Convex lens 2. Concave lens Convex lens ... thinner at the edges. Concave lens Concave lens is thinner in the middle and thicker at the edges.
Description : Ramsden eye-piece consists of (A) Two convex lenses short distance apart (B) Two concave lenses short distance apart (C) One convex lens and one concave lens short distance apart (D) Two Plano-convex lenses short distance apart, with the convex surfaces facing each other
Last Answer : (D) Two Plano-convex lenses short distance apart, with the convex surfaces facing each other
Description : Resolution by any microscope is ULTIMATELY limited by the: a) curvature of the lenses b) wavelength of the light c) light intensity d) lens aberrations
Last Answer : ANSWER: B -- WAVELENGTH OF THE LIGHT
Last Answer : A microscope that has two sets of lenses : an occular lens and an eyepiece.
Description : Which one of the following lenses should be used to correct the defect of astigmatism ? (1) Cylindrical lens (2) Concave lens (3) Convex lens (4) Bifocal lens
Last Answer : Cylindrical lens
Description : Two thin lenses of power `+ 3 D and - 1 D` are held contact with each other. Focal length of the combination is :
Last Answer : Two thin lenses of power `+ 3 D and - 1 D` are held contact with each other. Focal length of the combination is :
Description : Vehicles use ______ to see the objects coming from behind. (1) Concave lens (2) Convex lens (3) Convex mirror (4) Concave mirror
Last Answer : (2) Convex lens Explanation: Convex mirror is used in rear view mirror of vehicles; so that the driver can see the traffic coming from behind. The field of view is widest in case of a convex mirror, which enables it to show a wider area from behind.
Description : Vehicles use _____ to see the objects coming from behind. (1) Concave lens (2) Convex lens (3) Convex mirror (4) Concave mirror
Last Answer : Convex lens
Description : Which of the following can be used as a burning glass? (a) Plane mirror (b) Convex mirror (c) Concave lens (d) Concave mirror
Last Answer : Ans:(d)
Description : 4. A spherical mirror and a thin spherical lens have a focal length of -15 cm. The mirror and the lens are likely to be -Physics-10
Last Answer : (a) Both are likely to be concave.
Description : Draw the ray diagram in each case to show the position and nature of the image formed when the object is placed: (i) at the centre of curvature of a concave mirror (ii) between the pole P and focus F of ... front of a convex mirror (iv) at 2F of a convex lens (v) in front of a concave lens -Physics
Last Answer : Answer. Nature of image: Real, inverted and same size image is formed at the centre of curvature. Nature of image: Virtual, enlarged and erect image is formed behind the mirror. Nature of image: Virtual ... : Virtual, erect and diminished image is formed between O and F on the same side of object.
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 distance between a convex lens and a plane mirror is 15 cm. The parallel rays incident on the convex lens, after reflection from the mirror, form
Last Answer : The distance between a convex lens and a plane mirror is 15 cm. The parallel rays incident on the ... and find out the focal length of the lens.
Description : What is difference between lens and mirror with table?
Description : Which one of the following can be used to focus sunlight? A. Plane mirror B. Concave lens C. Concave mirror D. Convex mirror
Last Answer : ANSWER: C
Description : Why in Newton's rings setup, the beam splitter (mirror) is kept at 450? (a) It allows light rays to incident at 450over the top surface of Plano convex lens (b) It allows light rays to ... Plano convex lens (d) It allows light rays to incident at 900over the top surface of Plano convex lens
Last Answer : (d) It allows light rays to incident at 900over the top surface of Plano convex lens
Description : When beam of parallel rays of light falls on _______ then all the rays of light converge . a) convex lens b)concave lens c)plain mirror d)plano concave lens
Last Answer : a) convex lens
Description : By which one of the following can a real image be produced? Can it be produced by a: w) concave mirror x) plane mirror y) diverging lens z) convex mirror
Last Answer : ANSWER: W -- CONCAVE MIRROR
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 : What shape are the bacteria cells View under 100X objective lens power to see the shape.?
Last Answer : What is the answer ?
Description : What would be the total power if you used the 100X objective lens to view a specimen?
Description : How do you switch objective Lens?
Description : How do you find the total magnification of the eyepiece and the objective lens?
Description : Define objective lens?
Last Answer : The lens near the object to be seen is called objective lens?
Description : An internal focussing type surveying telescope, may be focussed by the movement of (A) Objective glass of the telescope (B) Convex-lens in the telescope (C) Concave lens in the telescope (D) Plano-convex lens in the telescope
Last Answer : (C) Concave lens in the telescope
Description : In an internal focusing telescope (A) The objective is at a fixed distance from the diaphragm (B) The focusing is done by the sliding of a divergent lens (C) The focusing divergent lens is situated at about the middle of the tube (D) All the above
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
Description : If a person looking through microscope at the full moon, how would the appearance of moon be changed by covering of objective lens?
Last Answer : Ans. He will observe the full image but its brightness will be reduced. In other word, the intensity of light will decreased.
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 : 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 : When the right combination of circumstances occurs at the right time to allow an organisation to take action toward a target market, the firm has identified a A)market objective. B)market requirement. C)strategic market plan. D)market opportunity. E)corporate objective.
Last Answer : D)market opportunity.