(iv) Twinkling of stars and non-twinkling of planets is accounted for by (iii) The sun appears oval shaped or flattened due to (ii) Apparent position of the star appears raised due toĪnswer: (a) Apparent position of the stars appears raised due to atmospheric refraction. (i) Due to atmospheric refraction, apparent length of the dayĪnswer: (a) Due to atmospheric refraction, apparent length of the day increases by 4 minutes. On account of atmospheric refraction, stars seen appear higher than they actual are advanced sunrise delayed sunset, oval appearance of the sun at sunrise and sunset stars twinkle, planets do not. also affect the optical density of earth’s atmosphere. As we move above the surface of earth, density of air goes on decreasing.
Read the following and answer any four questions from (i) to (v)Ītmospheric refraction is the phenomenon of bending of light on passing through earth’s atmosphere. (a) the red light can be seen from farthest distanceĪnswer: (c) Scattering is least but velocity of red light is more. (v) The danger signs made red in colour, because
(c) Green and blue scattered and orange reaches our eyeĪnswer: (a) Red light being the largest wavelength blue scatters more, red scattered least. (b) Red colour scattered and blue colour reaches our eye (a) Blue colour scattered and red colour reaches our eye (a) refraction of light through the atmosphereĪnswer: (c) Due to more scattering of blue colour by molecules of air. (iii) The colour of sky appears blue, it is due to the (ii) At the time of sunrise and sunset, the light from sun has to travel.Īnswer: (a) As the distance between us and the sun is more at the time of sunrise and sunset. (i) To an astronaut in a spaceship, the colour of earth appearsĪnswer: (b) Light is scattered by the air molecules present in the atmosphere. The path of sunlight entering in the dark room through a fine hole is seen because of scattering of the sun light by the dust particles present in its path inside the room. When light from sun enters the earth’s atmosphere, it gets scattered by the dust particles and air molecules present in the atmosphere. The amount of scattering of light depends on the wavelength of light. The smaller the molecules in the atmosphere scatter smaller wavelengths of light. The colour of the scattered light depends on the size of particles. The sun appears red at sunrise and sunset, appearance of blue sky it is due to the scattering of light. The light having least wavelength scatters more. The spreading of light by the air molecules is called scattering of light. Read the following and answer any four questions from (i) to (v). Here, we have provided case based/passage based questions for Class 10 Science Chapter 11 The Human Eye and The Colourful World. In that, a paragraph will be given, and then the MCQ questions based on it will be asked. There will be a few questions based on case studies and passage based as well. In CBSE Class 10 Science Paper, Students will have to answer some questions based on Assertion and Reason.