Q1. Which part of the eye can be donated after death?
Q2. Name the part of an eye which is equivalent to
(i) diaphragm and
(ii) photographic plate, in a camera.
Q3. How is the sense of vision carried from the eye to the brain?
Q4. Which liquid fill in the space between eye lens and retina?
Q5. What is the nature of an image formed on the retina of the eye?
Q6. A man is wearing glasses of focal length + 1 m, what can be defect in the eye?
Q7. What is the twinkling of stars due to?
Q8. On what factor does the colour of the scattered light depends?
Q9. Why are danger signal lights red in colour?
Q10. What would have been the colour of the sky, if the Earth had no atmosphere?
Q11. Bees are able to see ultraviolet light. Comment.
Q12. Define power of accommodation.
Q 13. What is the purpose of human eye?
Q14. State one function of iris in human eye.
Q15. What is the nature of image formed on the retina?
Q16. What is meant by dispersion of light?
Q17. What is tyndall effect?
Q18. Name the type of particles which acts as a prism in the formation of rainbow in the sky.
Q19. On which factor does the colour of the scattered white light depend?
Q20. The sky appears dark to passengers flying at a very high altitude. Why?
Q21. What is the cause of dispersion of light passing through a prism?
Q22. Which liquid is filled in the space between eye lens and retina?
Q23. Which part of eye acts as a cable which connects the eye with the brain?
Q24. What is the nature of the image formed on the retina? What kind of lens is present in our eye?
Direction (Q Nos. 25 – 29) In each of the following questions, a statement of Assertion is given by the corresponding statement of Reason. Of the statements, mark the correct answer as
(a) If both Assertion and Reason are true and Reason is the correct explanation of Assertion.
(b) If both Assertion and Reason are true, but Reason is not the correct explanation of Assertion.
(c) If Assertion is true, but Reason is false.
(d) If Assertion is false, but Reason is true.
(e) If Assertion and Reason both are false.
Q25. Assertion: The least distance of distinct vision for a young adult with normal vision is 20 cm.
Reason: Far point for a human eye with normal vision is infinity.
Q26. Assertion: Tyndall Effect is an optical phenomenon of light used to explain atmospheric refraction.
Reason: The tiny particles of dust disperse sunlight in it falls through foliage in a forest.
Q27. Assertion: On a clear summer night twinkling of stars is observed.
Reason: The twinkling of stars is caused by dispersion of star light by the atmosphere.
Q28. Assertion: On mid-day, the colour of the sunlight becomes white.
Reason: No atmospheric refraction is caused due to overhead sun.
Q29. Assertion: Ciliary muscles adjust the size of the crystalline lens inside the human eye.
Reason: Gradual weakening of ciliary muscles leads to astigmatism.
Q30. A person with a myopic eye cannot see object beyond -1.2 m distinctly. The power of the corrective lens used to restore proper vision is
(c) + 0.21 D
(d) +0.91 D
Q31. At noon the sun appears white as:
(a) light is least scattered
(b) all the colours of the white light are scattered away
(c) blue colour is scattered the most
(d) red colour is scattered the most
Q32. The danger signals installed at the top of tall buildings are red in colour. These can be easily seen from a distance because among all other colours, the red light
(a) is scattered the most by smoke or fog
(b) is scattered the least by smoke or fog
(c) is absorbed the most by smoke or fog
(d) moves fastest in air
Q33. A student sitting on the last bench can read the letters written on the blackboard but is not able to read the letters written in his textbook. Which of the following statements is correct?
(a) The near point of his eyes has receded away
(b) The near point of his eyes has come closer to him
(c) The far point of his eyes has come closer to him
(d) The far point of his eyes has receded away
Q34. What is dispersion? What happens when light is passed through a glass prism?
Q35. Why is it difficult to drive on a foggy day?
Q36. Explain, why the Sun overhead at noon, appears white?
Q37. Calculate maximum power of accommodation of a person having normal vision.
Q38. Name the parts of our eyes that help us to focus near and distant objects in quick succession.