See Our team
Wondering how we keep quality?
Got unsolved questions? Ask Questions
Engineering GATE CBSE NCERT Psychology English Computer Constitution Astrology Yoga Economics Physics Biology Electronics Microprocessor Career Interview Anatomy Botany
Never Miss an Update
Subscribe to eduladder news letter Today
Like to work with us?
A person needs a lens of power –5.5 dioptres for correcting his distant vision. For correcting his near vision he needs a lens of power +1.5 dioptre. What is the focal length of the lens required for correcting (i) distant vision, and (ii) near vis1 AnswerA student used a device (X) to obtain/focus the image of a well illuminated distant building on a screen ( S ) as shown below in the diagram. Select the correct statement about the device (X). CBSE- class10- Science 20151 AnswerA convex lens of focal length 25 cm and a concave lens of focal length 10 cm are placed in close contact with each other. Calculate the lens power of this combination. - 2008 CBSE Physic class 101 Answer Find the focal length of a lens of power – 2.0 D. What type of lens is this? -CBSE Physics1 AnswerA concave lens has focal length of 15 cm. At what distance should the object from the lens be placed so that it forms an image at 10 cm from the lens? Also, find the magnification produced by the lens. -CBSE Physics1 AnswerA concave lens has focal length of 15 cm. At what distance should the object from the lens be placed so that it forms an image at 10 cm from the lens? Also, find the magnification produced by the lens. -CBSE Physics1 Answer 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. -CBSE Physics1 AnswerWhat is meant by power of a lens? Define its SI unit. CBSE- class10- Science 20151 AnswerWhat is meant by power of a lens? Define its SI unit. CBSE- class10- Science 20151 AnswerDescribe with a neat diagram how this defect of vision can be corrected by using a suitable lens. -2008 CBSE Physic class 101 AnswerA person with a myopic eye cannot see objects beyond 1.2 m distinctly. What should be the type of the corrective lens used to restore proper vision? -CBSE Physics2 Answer Diameter of a plano - convex lens is 6 cm and thickness at the centre is 3 mm. If speed of light in material of lens is 2 × 108 m/s, the focal length of the lens is : - physics 20131 AnswerA 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 -2007 CBSE Physic class 101 AnswerThe image of a candle flame placed at a distance of 45 cm from a spherical lens is formed on a screen placed at a distance of 90 cm from the lens. Identify the type of lens and calculate its focal length. If t he height of the flame is 2 cm, f ind 1 AnswerFind the power of a concave lens of focal length 2 m. -CBSE Physics1 AnswerA student obtained a sharp inverted image of a distant tree on the screen placed behind a convex lens. He then removed the screen and tried to look through the lens in the direction of the object. He would now observe: CBSE class10 Science 20161 AnswerDefine 1 dioptre of power of a lens. -CBSE Physics1 Answer A concave lens of focal length 15 em forms an image 10 em from the lens. Calculate -2008 CBSE Physic class 101 Answer The far point of a myopic person is 80 cm in front of the eye. What is the nature and power of the lens required to correct the problem? - CBSE physics1 AnswerA 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? Also, find the power of the lens. -CBSE Physics1 Answer