1) white light enters water droplet, undergoes ____ and ____. (Rainbow) a) diffraction … dispersion b) reflection … refraction c) refraction … dispersion 2) _______ reflection occurs during the formation of rainbow. a) total internal b) internal c) total 3) light rays refracted and dispersed as it moves ____ __ water and ____ air. (Rainbow) a) to the top … into b) into … out of c) out of … into d) out of … evaporated into 4) Air above the road is _____ than upper layers. (Mirage) a) colder b) hotter 5) Hotter air has ____ optical density compared to cold air. (Mirage) a) smaller b) larger 6) Reflected light rays are _____ into observer's eyes. (Mirage) a) reflected b) diffracted c) interference d) refracted 7) Optical fibres are used in _____ and _____. a) telecommunications... medicine b) education ... Medicine c) education ... agriculture d) fast fashion ... Agriculture 8) Optical fibres made from ____ or ____. a) tempered glass ... plastic fibre b) pure glass ... plastic fibres c) pure glass ... biodegradable plastic 9) Prism periscope are used to see objects ____ barriers. a) behind b) on top of c) on front of d) within 10) Images formed by prism periscope is ___ and ___ size. a) flipped horizontally ... same b) upright ... same c) flipped vertically ... same d) upright ... different 11) Cat's eye reflector is used for ___ of road users at night. a) safety b) fun c) excitement d) regulation

Physics

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