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

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
by

1 Answer

Answer :

(D) All the above
by

Related questions

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 but nearer to the later (C) The outer component of the objective is a double-convex lens of crown glass (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

Last Answer : (D) All the above

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 combination of the lenses (C) In telescope objectives, a combination of convex lens and concave lens is used (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

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) The distance between the diaphragm and the front lens of the eyepiece is kept equal to 1/4 th of the focal length of a lens so that rays from a point on the diaphragm enter the eye as a parallel beam (D) All the above

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 

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

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 

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

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

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

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

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

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

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

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

Flint glass (A) Has slightly the greater refracting power than crown glass (B) Has roughly double refracting power than that of crown (C) And crown glass proportions yield the required focal length and neutralise the dispersion produced by the convex lens at the emergence from the concave (D) All the above

Description : Flint glass (A) Has slightly the greater refracting power than crown glass (B) Has roughly double refracting power than that of crown (C) And crown glass proportions yield the required focal length ... dispersion produced by the convex lens at the emergence from the concave (D) All the above

Last Answer : (D) All the above

The imaginary line passing through the intersection of cross hairs and the optical centre of the objective, is known as (A) Line of sight (B) Line of collimation (C) Axis of the telescope (D) None of these

Description : The imaginary line passing through the intersection of cross hairs and the optical centre of the objective, is known as (A) Line of sight (B) Line of collimation (C) Axis of the telescope (D) None of these

Last Answer : (B) Line of collimation

Diaphragm of a surveying telescope is held inside (A) Eye-piece (B) Objective (C) Telescope tube at its mid point (D) Telescope at the end nearer the eye-piece

Description : Diaphragm of a surveying telescope is held inside  (A) Eye-piece  (B) Objective  (C) Telescope tube at its mid point  (D) Telescope at the end nearer the eye-piece

Last Answer : (D) Telescope at the end nearer the eye-piece

Pick up the correct statement from the following: (A) For channels, the shear centre does not coincide its centroid (B) The point of intersection of the bending axis with the cross section of the beam, is called shear centre (C) For I sections, the shear centre coincides with the centroid of the cross section of the beam (D) All the above

Description : Pick up the correct statement from the following:  (A) For channels, the shear centre does not coincide its centroid  (B) The point of intersection of the bending axis with the cross section ... shear centre coincides with the centroid of the cross section of the beam  (D) All the above

Last Answer : (D) All the above

The real image of an object formed by the objective must lie (A) In the plane of cross hairs (B) At the centre of the telescope (C) At the optical centre of the eye-piece (D) Anywhere inside the telescope

Description : The real image of an object formed by the objective must lie (A) In the plane of cross hairs (B) At the centre of the telescope (C) At the optical centre of the eye-piece (D) Anywhere inside the telescope

Last Answer : (A) In the plane of cross hairs

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 : 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 

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

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 

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

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

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

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.

An object is placed beyond 2F, in front of a convex lens, image will be formed : (a) between F and 2F (b) at focus (c) at the centre of curvature (d) between focus and Optical centre

Description : An object is placed beyond 2F, in front of a convex lens, image will be formed : (a) between F and 2F (b) at focus (c) at the centre of curvature (d) between focus and Optical centre

Last Answer : (a) between F and 2F

When object is placed _______ in front of convex lens than image formed is virtual, erect, magnified and on same side beyond F . a) between optical centre and F b)At F c)between F and 2F d)2F

Description : When object is placed _______ in front of convex lens than image formed is virtual, erect, magnified and on same side beyond F . a) between optical centre and F b)At F c)between F and 2F d)2F

Last Answer : a) between optical centre and F

Pick up the correct statement from the following: (A) The lines of sight while observing back sight and fore sight lie in the same horizontal plane (B) The staff readings are measurements made vertically downwards from a horizontal plane (C) The horizontal plane with reference to which staff readings are taken, coincides with the level surface through the telescope axis (D) All the above

Description : Pick up the correct statement from the following: (A) The lines of sight while observing back sight and fore sight lie in the same horizontal plane (B) The staff readings are measurements made ... readings are taken, coincides with the level surface through the telescope axis (D) All the above

Last Answer : (D) All the above

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

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.

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

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

The locus of the moment of inertia about inclined axes to the principal axis, is (A) Straight line (B) Parabola (C) Circle (D) Ellipse

Description : The locus of the moment of inertia about inclined axes to the principal axis, is  (A) Straight line  (B) Parabola  (C) Circle  (D) Ellipse

Last Answer : (D) Ellipse

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 : 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

Last Answer : (D) All the above

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

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

Pick up the correct statement from the following: (A) The eyepiece plays no part in defining the line of sight (B) The diaphragm plays no part in defining the line of sight (C) The optical centre of the objective plays no part in defining the line of sight (D) None of these

Description : Pick up the correct statement from the following: (A) The eyepiece plays no part in defining the line of sight (B) The diaphragm plays no part in defining the line of sight (C) The optical centre of the objective plays no part in defining the line of sight (D) None of these

Last Answer : (A) The eyepiece plays no part in defining the line of sight

If f1 and f2 are the distances from the optical centre of a convex lens of focal length to conjugate two points P1 and P2 respectively, the following relationship holds good (A) f = f1 + f2 (B) f = ½ (f1 + f2) (C) 1/f = 1/f1 + 1/f2 (D) None of these

Description : If f1 and f2 are the distances from the optical centre of a convex lens of focal length to conjugate two points P1 and P2 respectively, the following relationship holds good (A) f = f1 + f2 (B) f = ½ (f1 + f2) (C) 1/f = 1/f1 + 1/f2 (D) None of these

Last Answer : (C) 1/f = 1/f1 + 1/f2

Pick up the correct statement from the following: (A) The bending stress in a section is zero at its neutral axis and maximum at the outer fibres (B) The shear stress is zero at the outer fibres and maximum at the neutral axis (C) The bending stress at the outer fibres, is known as principal stress (D) All the above

Description : Pick up the correct statement from the following:  (A) The bending stress in a section is zero at its neutral axis and maximum at the outer fibres  (B) The shear stress is zero at the outer ... (C) The bending stress at the outer fibres, is known as principal stress  (D) All the above 

Last Answer : (D) All the above 

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.

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).

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.

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.

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

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

What is lens? Explain the difference between convex and concave lenses.

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.

Pick up the correct statement from the following: (A) In the earth's magnetic field, a magnetic needle rests in magnetic meridian (B) The angle between the true meridian and the magnetic meridian is called magnetic variation (C) One end of the magnetic needle supported at its centre of gravity tends to dip down towards the nearer magnetic pole of the earth (D) All the above

Description : Pick up the correct statement from the following: (A) In the earth's magnetic field, a magnetic needle rests in magnetic meridian (B) The angle between the true meridian and the magnetic meridian is ... gravity tends to dip down towards the nearer magnetic pole of the earth (D) All the above

Last Answer : (D) All the above

An object nearer to a converging lens than its focal point always has a/an ______ image. a. Inverted b. The same in size c. Virtual d. Smaller size

Description : An object nearer to a converging lens than its focal point always has a/an ______ image. a. Inverted b. The same in size c. Virtual d. Smaller size

Last Answer : c. Virtual

An object nearer to a converging lens than its focal point always has a/an ______ image. ∙ a. Inverted ∙ b. The same in size ∙ c. Virtual ∙ d. Smaller size

Description : An object nearer to a converging lens than its focal point always has a/an ______ image. ∙ a. Inverted ∙ b. The same in size ∙ c. Virtual ∙ d. Smaller size

Last Answer : c. Virtual

Knuckle Joint is used to connect the two rods whose axes are coincide or intersect and lies in the same plane. A. True B. False

Description : Knuckle Joint is used to connect the two rods whose axes are coincide or intersect and lies in the same plane. A. True B. False

Last Answer : A. True

The knuckle joint is used to connect the... A. Two roads whose Axes are coincide or intersecting and lies in single plane. B. Two roads whose Axes are coincide or intersecting and lies in multiple plane. C. Two roads whose Axes are parallel or intersecting and lies in single plane. D. None of the above

Description : The knuckle joint is used to connect the... A. Two roads whose Axes are coincide or intersecting and lies in single plane. B. Two roads whose Axes are coincide or intersecting and lies in multiple ... Two roads whose Axes are parallel or intersecting and lies in single plane. D. None of the above

Last Answer : A. Two roads whose Axes are coincide or intersecting and lies in single plane.

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

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

How does reflecting telescope differ from refracting telescope?

Description : How does reflecting telescope differ from refracting telescope?

Last Answer : Reflecting telescope can be made much larger than a refracting telescope, so that a better and bright image can be seen.

Large astronomical telescopes always use as objective (a) Lens (b) Mirror (c) Combination of lenses (d) None of the above

Description : Large astronomical telescopes always use as objective (a) Lens (b) Mirror (c) Combination of lenses (d) None of the above

Last Answer : Ans:(a)

The lens equation 1/f = 1/ + 1/ is applicable (A) When the thickness of the lens is small (B) Only to conjugate distances along the principal axis (C) The computed quantities are accurate enough for geometrical optics of simple distances (D) All the above

Description : The lens equation 1/f = 1/ + 1/ is applicable (A) When the thickness of the lens is small (B) Only to conjugate distances along the principal axis (C) The computed quantities are accurate enough for geometrical optics of simple distances (D) All the above

Last Answer : (D) All the above

Pick up the incorrect statement from the following. Intake of water supply should (A) Be nearer to the treatment plant (B) Receive water from purer zone of the source (C) Be located downstream of waste water disposal point (D) Remain easily accessible during floods

Description : Pick up the incorrect statement from the following. Intake of water supply should  (A) Be nearer to the treatment plant  (B) Receive water from purer zone of the source  (C) Be located downstream of waste water disposal point  (D) Remain easily accessible during floods 

Last Answer : (C) Be located downstream of waste water disposal point 

In a perfect prismatic compass (A) Magnetic axis and geometric axis of the needle coincide (B) Ends of the needle and pivot are in same vertical and horizontal planes (C) Pivot is vertically over the centre of the graduated circle (D) All the above

Description : In a perfect prismatic compass (A) Magnetic axis and geometric axis of the needle coincide (B) Ends of the needle and pivot are in same vertical and horizontal planes (C) Pivot is vertically over the centre of the graduated circle (D) All the above

Last Answer : (D) All the above

A simple microscope consists of : (1) a short focus convex lens (2) a long focus convex lens (3) a short focus concave lens (4) a long focus concave lens

Description : A simple microscope consists of : (1) a short focus convex lens (2) a long focus convex lens (3) a short focus concave lens (4) a long focus concave lens

Last Answer : (1) a short focus convex lens Explanation: Simple microscope - light microscope consisting of a short focus single convex lens is used to produce an enlarged image. The magnifying glass was ... object viewed and one lens, increasing the visibility of the object by some amount (magnification).

A simple microscope consists of : (1) a short focus convex lens (2) a long focus convex lens (3) a short focus concave lens (4) a long focus concave lens

Description : A simple microscope consists of : (1) a short focus convex lens (2) a long focus convex lens (3) a short focus concave lens (4) a long focus concave lens 

Last Answer :  a short focus convex lens

A needle 10 cm long is placed along the axis of a convex lens of focal length 10 cm such that the middle point of the neddle is at a distance of 10 cm

Description : A needle 10 cm long is placed along the axis of a convex lens of focal length 10 cm such that the middle point of the neddle is at a distance of 10 cm

Last Answer : A needle 10 cm long is placed along the axis of a convex lens of focal length 10 cm such that ... lens. Find the length of the image of the neddle.

Pick up the correct statement from the following: (A) The theodolite in which telescope can be rotated in vertical plane is called a transmit (B) When the vertical circle is to the left of the telescope during observation, it is called to be in left face (C) When the vertical circle is to the right of the telescope during observation, it is called to be in right face (D) All the above

Description : Pick up the correct statement from the following:  (A) The theodolite in which telescope can be rotated in vertical plane is called a transmit  (B) When the vertical circle is to the left of ... the telescope during observation, it is called to be  in right face  (D) All the above 

Last Answer : (D) All the above 

When you are focusing on a object in which order should the three objective lenses always be used?

Description : When you are focusing on a object in which order should the three objective lenses always be used?

Last Answer : Need answer

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

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.