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- Q) why coal and petroleum are called fossil fuel?
- Q) " sun is the ultimate source of energy of fossil fuels". justify
- Q) 3. why do we need to manage our resources?
- Q) q11. what are the problems addressed by the cruiser’s about large dams? q12. what is ovulation & when does it takes place during the menstrual cycle? where the fertilization does takes place? q13. what are sexually transmitted diseases? name four such diseases. which one of them damaged the immune? q14. (a) an 8cm tall object is placed perpendicular to the principle axis of a convex lens of focal length 25cm. the distance of the object from the lens is 30cm. find the position, nature and size of the image formed? q15. show hypermetropic eye defect with a ray diagram. which type of lens is suitable to correct this defect? show with a diagram a corrected vision. q16. (a) why is the refractive index of a medium always greater than one? explain briefly. (b) the refractive index of a diamond is 2.42. what is the meaning of this statement? q17. what is esterification? what are its uses? q18. compare & contrast the arrangement of elements in the mendeleev’s periodic table & modern periodic law. q19. how evolution occurred by a single ancestral linkage? q20. how have feathers evolved? explain. q21. what is the contribution of mendel in genetics? q22. describe the reproductive system of a human male. q23. when a magnifying glass converges the sun’s rays on a sheet of paper, it starts burning. why? or an object is placed at a point between infinity & optical centre o in front of a concave lens. using a ray diagram, explain the image formation. what are the properties of the image? or describe an activity to plot the refraction of a light ray through a parallel glass slab. q24. complete the following equation: (a) ch4(g) + o2(g) (b) ch3cooc2h5 + naoh (c) ch3ch2oh alkaline (heat) kmno4 q25. (a) how does the embryo get nourishment inside the mother’s body? (b) what are the functions of testes in human males? (c) why does mensuration occur? or (a) what are the different methods of contraception? (b) where are the vegetative buds present in bryophyllum? (c) where does the formation of dna copy occurs? section-b q26. consider the given diagram. which of the path out of 1, 2 and 3 is followed by a light ray r after reflection from the mirror? (a) 1 (b) 2 (c) 3 (d) none of these q27. three students measured the focal length of a convex lens using parallel rays from a distant object. all of them measured the distance between the lens and the inverted image on the screen. student a saw a sharp image on the screen and labelled the distance as f1. student b saw a slightly larger blurred image on the screen and labelled the distance as f2. student c saw a slightly smaller blurred image on the screen and labelled the distance as f3. the relation between the three measurements would most likely be (a) f1 = f2 = f3. (b) f1 < f2 and f3. (c) f3 < f1 < f2. (d) f1 < f2 and f1= f3. q28. in concave mirror, the image formed is always bigger than the size of object when the object is placed: (i) at principal focus. (ii) at centre of curvature. (iii) beyond centre of curvature. (iv) between pole and focus. the write choice is: (a) (i) only (b) (i) and (iii) (c) (ii) only (d) (i) and (iv) q29. an object is kept 15 cm in front of a concave lens of focal length 20 cm. if the object is moved by 3 cm towards the lens, by what factor will the magnification change? (a) 20/19 (b)3/5 (c) 35/32 (d)9/5 q30. what is the nature and size of the image formed when an object is placed at focus f1 of a convex lens? (a) virtual and erect, enlarged (b) real and inverted, diminished (c) virtual and erect, diminished (d) real and inverted, enlarged q31. which of the following structures correctly represents the electron dot structure of a water molecule? (a) (b) (c) (d) q32. which of the following compounds is first in the alkyne series? (a) methyne (b) ethyne (c) propyne (d) ethylene q33. the element ‘eka–aluminium’ predicted by mendeleev is ________. (a) boron (b) silicon (c) gallium (d) aluminium q34. which of the following orders of elements is correct in terms of decreasing atomic size? (a) f > cl > br (b) k > rb > cs (c) b > c > n (d) s > p > si q35. which of the following carbon compounds has the highest melting point? (a) acetic acid (b) calcium carbonate (c) ethanol (d) methane q36. in the following figure: figure (a), (b) and (c) indicates the point of focus in case of (a) the normal eye, the hypermetropic eye and myopic eye (b) the hypermetropic eye, the myopic eye and normal eye (c) the normal eye, the myopic eye and hypermetropic eye (d) the myopic eye, the normal eye and hypermetropic eye q37. which of the following does not have a well–defined nucleus in its cells? (a) tiger (b) rose flower (c) bacteria (d) mushroom q38. an organ ‘x’ in three different species a, b and c has similar structure and becomes more complex on going from a b c. then, which of the following statement is true? (a) a, b, c have separate evolutionary origins (b) a, b, c have common evolutionary origins (c) a, b, c are not different but form a single species. (d) a is more evolved than c. q39. what is the accumulation of non–biodegradable substances at each trophic level referred to as? (a) food web (b) biological magnification (c) decomposition (d) fermentation q40. which part of bryophyllum plant helps in vegetative propagation? (a) roots (b) leaves (c) stem (d) flowers q41. a mendelian experiment consisted of breeding tall pea plants bearing violet flowers with short pea plants bearing white flowers. the progeny all bore violet flowers, but almost half of them were short. this suggests that the genetic make-up of the tall parent can be depicted as (a) ttww (b) ttww (c) ttww (d) ttww
- Q) name the 2 elements present in cng and petroleum. also name if any are common between the two.