Description : 1. A convex lens of glass has power P in air. If it is immersed in water, what will be its power? 2. The internal secretion of which acid helps in digestion? 3. Who is responsible for ... 19. 17th Parallel separates which country? 20. Who established Fergusson College at Pune in the year 1885 ?
Last Answer : Answer : 1. Less than P 2. Hydrochloric acid 3. Election Commission 4. Asia 5. Gopala 6. Direct tax 7. Shooting 8. Acetylene 9. Titusfills in Pennsylvania, U.S.A. 10. Makrana marble 11 ... Demand draft 17. Infra-red-waves 18. Permanent tissue 19. North and South Vietnam 20. Deccan Education Society
Description : A double convex lens has radii 20 cm. The index of refraction of glass is 1.5. Compute the focal length of this lens in air and when immersed in carbo
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 thin convex lens of glass is `5 dioptre`. When it is immersed in a liquid of refractive index `mu`, it behave like a diverging lens of
Last Answer : The power of a thin convex lens of glass is `5 dioptre`. When it is immersed in a liquid of refractive index ... liquid, if `mu` of glass `= 3//2`.
Description : A convex lens of refractive index 1.5 is immersed in a liquid of refractive index (i) 1.6 (ii) 1.3 and (iii) 1.5. what changes happens to the focal le
Last Answer : A convex lens of refractive index 1.5 is immersed in a liquid of refractive index (i) 1.6 (ii) ... the focal length of the lens in the three cases ?
Description : 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)`.
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 : The focal length of a plano-convex lens is 20 cm in air. Refractive index of glass is 1.5. Calculate (i) the radius of curvature of lens surface and (
Last Answer : The focal length of a plano-convex lens is 20 cm in air. Refractive index of glass is 1.5. ... length when immersed in liquid of refractive index 1.6
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
Description : The radii of curvatureof double convex lens of glass `(mu = 1.5)` are in the ratio of `1 : 2`. This lens renders the rays parallel coming from an illu
Last Answer : The radii of curvatureof double convex lens of glass `(mu = 1.5)` are in the ratio of `1 ... 6 cm`. Calculate the radii of curvature of its surfaces.
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 : Magnifying Glass is basically a – (1) Plano-concave lens (2) Concave lens (3) Convex lens (4) Cylindrical lens
Last Answer : (3) Convex lens Explanation: A magnifying glass is a convex lens that is used to produce a magnified image of an object. The magnification of a magnifying glass depends upon where it is placed between the user's eye and the object being viewed, and the total distance between them.
Description : Which of the following is used to split white light into different colours? (1) Glass slab (2) Convex lens (3) Concave lens (4) Prism
Last Answer : (4) Prism Explanation: In optics, a prism is a transparent optical element with flat, polished surfaces that refract light. At least two of the flat surfaces must have an angle between them. The ... a triangular base and rectangular sides, and in colloquial use "prism" usually refers to this type.
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 : 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 : Newton's rings are formed because of interference between the light Reflected from (a) Upper surface of Plano-convex lens and lower surface of plane glass plate (b) Lower surface of Plano-convex ... c) Lower and upper surface of Plano-convex (d) Lower and upper surfaces of plane glass plate
Last Answer : (b) Lower surface of Plano-convex lens and upper surface of plane glass plate
Description : Magnifying Glass is basically a (1) Plano-concave lens (2) Concave lens (3) Convex lens (4) Cylindrical lens
Last Answer : Convex lens
Description : Which of the following is used to split white light into different colours ? (1) Glass slab (2) Convex lens (3) Concave lens (4) Prism
Last Answer : Prism
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 : The figure shows the front view of a convex lens, which originally had only one edge. Five holes of different shapes, namely triangle, square, pentagon, hexagon and circle, were drilled through it at points P ... . What is the total number of edges in the lens after the holes were drilled?
Last Answer : 57
Description : A thin glass prism placed in air produces minimum deviation of `4^(@)` in a light ray. If the prism is immersed in water, what will be the minimum dev
Last Answer : A thin glass prism placed in air produces minimum deviation of `4^(@)` in a light ray. If the prism is immersed in ... //2` and `.^(a)mu_(w) = 4//3`.
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
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
Description : The focal length of a convex lens is 50 cm. what is its power?
Last Answer : +2 D
Description : The power of a lens (A) Is reciprocal of its focal length (B) Is positive if it is a convex lens (C) Is negative if it is a concave lens (D) Is measured in Diopter
Last Answer : (D) Is measured in Diopter
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 : 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
Description : Find the focal length and power of a convex lens, which when placed in contact with a concave lens of focal length `25 cm` forms a real image `5` time
Last Answer : Find the focal length and power of a convex lens, which when placed in contact with a concave ... the object placed `20 cm` from the combination.
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 : The focal length of a concave-convex lens of radii of curvature 5 cm and 10 cm is 20 cm. what will be its focal length in water ? Given `.^(a)mu_(w) =
Last Answer : The focal length of a concave-convex lens of radii of curvature 5 cm and 10 cm is 20 cm. what will be its ... water ? Given `.^(a)mu_(w) = 4//3`.
Description : Give reason: When a glass test tube containing a mixture of chloroform and acetone is immersed in water will disappear.
Last Answer : The mixture of acetone and chloroform has the same refractive index as that of the glass. The surface of glass will not reflect light. Hence the test tube appears to disappear.
Description : Give reason: Glass bottle immersed in a vessel filled with water does not break even when water beings to boil.
Last Answer : Glass is a bad conductor of heat.
Description : A convex surface of radiys of curvature 20 cm separates air from glass of refractive index 1.5. Find the position and the nature of the image of a sma
Last Answer : A convex surface of radiys of curvature 20 cm separates air from glass of refractive index 1.5. Find ... at 50 cm in front of the convex surface.
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 : 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 : The radii of curvature of each surface of a convex lens is `20 cm` and the refractive index of the material of the lens is `3//2` (i) Calculate its fo
Last Answer : The radii of curvature of each surface of a convex lens is `20 cm` and the refractive index of the ... What happens if the lens is cut along `CD` ?
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 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 : 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 : 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 : 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 : 12. Draw ray diagrams to represent the nature, position and relative size of the image formed by a convex lens for the object placed: -Chemistry-10
Last Answer : Answer. hope this helps you
Description : 9. One-half of a convex lens is covered with a black paper. Will this lens produce a complete image of the object? Verify your answer experimentally. Explain your observations. -Physics-10
Last Answer : Yes, it will produce a complete image of the object, as shown in the figure. This can be verified experimentally by observing the image of a distant object like a tree on a screen when the ... the lens is covered with a black paper. However, the intensity or brightness of the image will reduce.
Description : 3. Where should an object be placed in front of a convex lens to get a real image of the size of the object? -Physics-10
Last Answer : (b) The object should be placed at twice the focal length
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 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
Description : What is a convex lens ?
Last Answer : A convex lens is a lens that has a thick center and a narrow end.
Description : What is the shape of convex lens ?
Last Answer : The center of a convex lens is thicker and the edges are narrower
Description : What kind of reflection does a convex lens produce ?
Last Answer : Convex or convergent lenses form real and inverted reflections.
Description : What is the way to recognize convex lens ?
Last Answer : To easily recognize a lens, you have to place a finger very close to the lens and look at it from the other side. If the reflection is congruent and larger in size than the object, then the lens is convex.
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.