MP Board Class 10th Science Solutions The Human Eye And The Colourful World
Ans. “The pattern of colours obtained by dispersion of white light is called spectrum”.
Ans. (i) Yellow, (ii) Magenta, (iii) Peacock blue.
Q.4. What are pigments?
Ans. The coloured substance which are used in paints are known as pigments.
Q.5. What are the complementary colours ? Give example. (mp 2014)
Ans. The two colours of light by superposition of which white light is obtained are called complementary colours of light.
obviously yellow, peacock blue and magenta are complementary colours of blue, red and green colours respectively.
The Human Eye And The Colourful World
Short Answer Type QuestionS
Q.1. Write the names of those three primary colours which when mixed in suitable ratio produce white light.(mp 2016)
Ans. Red,Green and Blue are called primary colours which when mixed suitable ratio produce white light. Apart from this, these primary colours when mixed with their complementary colour produce white light.
Q.2. Write down uses of lenses.(mp 2010, 17)
Ans. (A) Uses of convex lenses: (i) These lenses are used as microscope, telescopes and camera etc.
(ii) These lenses are used to correct the long sightedness and presbyopia
(iii) They are used as magnifying glass by watch maker.
(iv) They are used as reading lenses.
(v) They are used by palmist and fingerprint experts.
(B) Uses of concave lenses: (i) In Galilean telescope.
(ii) These lenses are used to correct the short sightedness.
(C) Uses of cylindrical lenses
Q.3. What is short sightedness and long sightedness ? Explain by diagram that how it can be removed. (mp 2014, 17 )
Ans. Short sightedness: Person cannot see the distant objects clearly. It can be removed by using concave lens.
Long sightedness: Person cannot see the nearby objects clearly. It can be removed by using convex lens.