Important Questions, Science, Class 10 Board

Important Questions

Science

Std: 10                                                                                               Max. Marks : 100

MCQ

                                                                                                                                                    5 * 1 = 5

 1. Which of the following is liquid at ordinary temperature?

(a) Germanium      

(b) Gallium

(c) Gold

(d) Galena

2. The reducing agent used in the blast furnace to reduce Fe₂O₃ to Fe is

(a) coke

(b) carbon

(c) lime stone

(d) carbon monoxide

 3. Speciation occurs as a result of:

(a)reproductive isolation

(b)natural selection

(c)genetic drift

(d)all of these

 4. Which one of the following diseases is transmitted through sexual contact?

(a) Cancer

(b) AIDS

(c) Tuberculosis

(d) Diabetes

  

5. In a hydel station, the motion produced in turbines is due to the

(a) burning of coal

(b) burning of diesel

(c) flow of water

(d) production of steam.

 Very Short Answer Type Questions - 1 Mark

                                                                                                                                                   10 * 1 = 10

 1. Elements with eight electrons in their outermost energy shell are called_____.

 2. Can steel be used for making electromag­nets?

  

3. Which is the major constituent of biogas ?

  

4. Which element has twice as many electrons in its second shell as in its first shell ?

 5. In a solution of lead nitrate, a strip of metal 'M' was dipped. After some time, lead from the solution was deposited on the metal strip. Which metal is more reactive, M or lead?

6. Where are sperms deposited during sexual intercourse?

  

7. Can we change the polarity of a permanent magnet?

  

8. Interbreeding among individuals of different populations of a species maintains a free flow of genes in these populations.

  

9. Write word equation and then balanced chemical equation for the reaction taking   place when dilute sulphuric acid reacts with aluminium powder

 10. Who are the nature and wildlife enthusiasts?

 Short Answer Type Questions - 2 Mark

                                                                                                                                                  10 * 2 = 20

 1. Did Dobereiner's triads also exist in the columns of Newlands' law of octaves ? Explain your answer.

  

2. How are the lungs designed in human beings to maximize the area for exchange of gases?

  

3. Explain why, respiration is considered an exothermic reaction.

 4. What are the special features of commercial electric motors ?

 5. What are the advantages and limitations of using carbon as a reducing agent in the metallurgy?

  

6. What type of hydrocarbons give substitution reactions ? Which of the following hydrocarbons will give a substitution reaction?

CH₄;C₃H₆;C₃H₈;C₄H₆;C₅H₁₂;C₅H₁₀

 7. Why is it necessary to clean an aquarium once in a while?

 8. A colourless lead salt, when heated, produces a yellow residue and brown fumes :

(a) Name the lead salt.

(b) Name the brown fumes.

(c) Write chemical equation of the reaction involved

(d) Name the type of chemical reaction which takes place.

  

9. What are fossil fuels ? Give examples of fossil fuels and state their uses.

 10. Name different kinds of waste materials generated in the household. Classify them into biodegradable and non ­biodegradable.

 Short Answer Type Questions - 3 Mark                                                                                                                                                    10 * 3 = 30

1. What is geothermal energy ? Explain how geothermal energy is used to generate electricity.

 2. Give examples to explain the transforma­tion of potential energy into kinetic energy and vice versa.

  

3. How does phototropism occur in a plant stem (or shoot) ? Describe its mechanism. (This question can also be asked as : Explain the bending of a plant stem towards sunlight).

  

4. What do you mean by a solenoid? With the help of a labelled diagram, show the mag­netic field due to a current carrying solenoid.

  

5. Briefly explain the phenomenon earthing using examples.

 6. What are the two types of flames produced by the burning of fuels? How are these flames produced?

  

7. What is the general formula of the homologous series of alkanes? Write the names and formulae of the first four members of the homologous series of alkanes?. Give one point of difference between them.

 8. How will you demonstrate transpiration?

9. How does our body respond when adrenaline is secreted into the blood ?

  

10. What are the functions of (a) teeth (b) tongue?

 Long Answer Type Questions - 5 Mark

                                                                                                                                                     7 * 5 = 35

1. What is solar energy? How do form a solar panel cell? What are the uses of solar cells?

 

2. What is the relationship between

(a) oxidation and oxidising agent, and

(b) reduction and reducing agent in a redox reaction?

Write an example of a redox reaction showing above relationships.

  

3. Describe double circulation in human beings. Why is it necessary?

  

4. What are alloys? What are the general properties of alloys? List some important alloys along with their uses.

  

5. What are solar cells? How are they de­signed? Does solar energy cause any envi­ronmental pollution? State important uses of solar cells.

 6. Draw a labelled sketch to show the domestic electric wiring from an electric pole to a room. In this diagram show live wire, neutral wire, earth wire, main fuse, electric meter, main switch, consumer's fuse and wiring for a bulb and a three-pin socket. Also describe it briefly.

 7. In the Modern Periodic Table, calcium (atomic number 20) is surrounded by elements with atomic numbers 12,19 and 38. Which of these have physical and chemical properties resembling calcium?

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Objective Questions Mathematics, Class 10 Board

Mathematics

Std: 10                                                                                               Max. Marks : 100

Very Short Answer Questions - One Mark                                                                        100 * 1 = 100

1.

2. A sector with central angle 63°, cut out from a circle, contains 19.8 cm². Find the radius of the circle.

3. Solve for x and y:

4.

5. State whether the following are true or false. Justify your answer.

(i) The value of tan A is always less than 1.

 

(iii) cot A is a product of cot and A.

6. D and E are the points on the sides AB and AC, respectively of a ΔABC. If AB = 12 cm, AD = 8 cm, AE = 12 cm and AC= 19 cm, show that DE is parallel to BC.

7. If D and E are respectively the points on the AB and AC of a ΔABC such that AB = 12 cm, AD = 8 cm, AE = 12 cm, AC = 18 cm, show that DE || BC.

8. It is known that a box of 600 electric bulbs contains 12 defective bulbs. One bulb is taken out at random from this box. What is the probability that it is a non-defective bulb ?

9. Find the mean of the following data:

Class Interval	25-35	35-45	45-55	55-65	65-75
Frequency	6	10	8	12	4

10. A circular ground whose diameter is 35 metres, has a 1.4 m broad garden around it. What is the area of the garden?

11. Given that L.C.M. (480, 672) = 3360, find H.C.F. (480, 672).

12. For the following APs, write first term and common difference.

(i)  4,1,-2,-5, ... (ii) -3, 1, 1,3, ...

(iv) 0.7, 1.6, 2.5, 3.4, ...

13. Find the mean of the following data.

Class	0-100	100-200	200-300	300-400	400-500
Frequency	6	9	15	12	8

14. Find the value of x, if the distance between the points (x, - 1) and (3, 2) is 5.

15. Which term of the Arithmetic Progression 3, 10, 17...., will be 84 more than its 13^th term?

16. Write down the decimal expansions of those rational numbers in the following which have terminating, decimal expansions.

17. In the adjoining figure, if DE ||BC and AD = (4x - 3) cm, AE = (8x- 7)cm, BD=(3x-1)cm and CE = (5x - 3) cm, find x.

18. Cards marked with numbers 3, 4, 5, 50 are placed in a box and mixed thoroughly. One card is drawn at random from the box. Find the probability that the number on the drawn card is

(i) divisible by 7

(ii) a number which is a perfect square

19. The 8th term of an Arithmetic Progression is 37 and its 12th term is 57. Find the A.P.

20. Which term of the sequence 36, 31, 26, 21, 16,....is the first negative term?

21. For the following system of equations, find the value(s) of p so that the system has a unique solution.

(i) px + 2y = 5; 3x + y - 1 = 0

(ii) px + 3y - 7 = 0; 2x -y = 6

(iii) 9x + py= 1; 3x + 4y = 2.

22. Write first five terms of an AP if

(i) a = 2, d = 3 

(ii) a = 10, d = 6

(iii) a = 44, of = -4

(iv) a = 7,d = -7

23.

24. In ΔABC ÐB = ÐC and D and E are points on AB and AC such that BD = CE. Prove that DE||BC.

25. D and E are two points on the sides AB and AC of ΔABC such that AD = 5cm, DB=7 cm, AE = 6cm and EC = 9cm. Determine whether DE || BC.

26. If the radius of a sphere is increased by 2 cm, then its surface area increases by 352 cm². What was the radius of the sphere before the increase ?

27. Find the point on the x-axis which is equidistant from the points (-2, 5) and (2, -3).

28. A dice is tossed once. What is the probability of the dice coming up with a number < 8 ? What is the probability of the dice coming up with the number 8?

29. Which of the following sequences are in AP.

(i) 1,2,3,4,5,6, ......

(ii) 3,6,9, 12, ......

(iii) 2,4,8, 16, 32,.....

(iv) 2², 2⁴, 2⁶, 2⁸, ......

(v) 2², 3², 4², 5², ......

(vi) a⁰, a², a⁴, a⁶.......

(vii) 95, 90, 85, 80,......

30. Solve the quadratic equation : (3x - 4) (3x - 2) = 0.

31. The volume of a right circular cylinder is 1100 cu.cm and the radius of its base is 5 cm. Find its curved surface area.

32. Find the first three terms of a sequence whose nth term is given by t _n =2n+ 1.

33. The circumference of the edge of a hemispherical bowl is 132 cm. Find the capacity of the bowl. (Take p=  )

34. Fill in the blanks using the correct word given in brackets.

(i) All circles are ... (congruent, similar)

(ii) All squares are ... (similar, congruent)

(iii)All ... triangles are similar (equilateral, isosceles)

(iv) Two polygons of the same number of sides are similar if (a) their corresponding angles are…

(b) their corresponding sides are…. .....

35. In the adjoining figure, ΔABC and ΔCPD are right angled at B and P respectively.

36. Find the 8th term from the end of the A.P. 7, 10, 13,...., 184.

37. Show that the system of equations 3x + 4y =7; 12x+ 16y = 28 has infinitely many solutions.

38. Find the area of a sector of a circle with radius 14 cm and angle of sector is 60°.

39. Find the cubic polynomial with the sum of its zeros, sum of the products of its zeros taken two at a time and the product of its zeros as 10, 11 and - 70 respectively.

40. If one of the zeros of the quadratic polynomial 2x² + kx - 12 is - 4, find the value of k.

41. A horse is placed for grazing inside a rectangular field 70 m by 52 m. It is tethered to one corner by a rope 21 m long. On how much area can it graze? How much area is left ungrazed?

42. The circumference of a circle exceeds its diameter by 16.8 cm. Find the circumference of the circle.

43. In 56, 63, 70,......, 497 series, how many terms are there?

44. In the given figure, sectors of two concentric circles of radii 7 cm and 3.5 cm are shown. Find the area of the shaded region.

45.

46.

47. The height of a cylinder is 15 cm. The curved surface area is 660 sq. cm. Find its radius.  (Take p= )

48. Find the common difference of the A.P. whose 11th term is 5 and 13th term is 79. What is the 24th term?

49. Eleven balls are serially numbered and placed in an urn. Find the probability that a ball drawn will be:

(i) odd numbered ball

(ii) even numbered ball

(iii) prime numbered ball

50. The end points of the diameter of a circle are (2, -1) and (5, 4). Find the co-ordinates of the centre.

51. Check whether the following are quadratic equations?

                                    

(iii) (x-1) (x+4) =  x² +1

52. The zeros of the quadratic polynomial x² + 4x + k are  α and β. Find the value of k if 5α + 2β = 1.

53. For what value of k will the terms (2k + 1), 8 and 3 k form an A.P.?

54. Show that the points (a, b + c), (b, c + a) and (c, a + b) are collinear.

55. The coordinates of the midpoint of the line joining the points (2p + 2, 3) and (4, 2q +1) are (2p,2q). Find the values of p and q.

56.

57.

58. Prove that : (sec²q -1) cot²q =1.

59.

60. If α and β are the zeros of the quadratic polynomial p(x)=ax² + bx + c ,then evaluate :

61. In right triangle ACB, ÐC = 90°, AB = 29 units and BC = 21 units. If ÐABC = θ, find cos² θ - sin² θ and sin² θ + cos² θ

62. A circular garden has a circumference of 440 m. There is a 7 m wide path inside the garden along its periphery. Find the area of the path.

63. If one of the zeros of the polynomial 3x² - 10x + (2k - 1) is a reciprocal of the other,  then evaluate the value of k.

64. The diagonal AC of a quadrilateral ABCD bisects both ÐA and ÐC. Prove that

65. The coordinates of two vertices A and B of a triangle ABC are (1, 4) and (5, 3) respectively. If the coordinates of the centroid of  DABC are (3, 3), find the coordinates of the third vertex C.

66. If 7 times the 7th term of an A.P. is equal to 11 times the 11th term, show that its 18^th term is zero.

67. A (7, 0), B (0, - 24) and O (0, 0) are the vertices of a triangle. Calculate the length of the hypotenuse of right angled DAOB.

68. Prove that the product of a rational and an irrational number is irrational.

69. By distance formula, show that the points (1, - 1), (5, 2) and (9, 5) are collinear.

70. The area of the sector of a circle of radius 17.5 cm is 192.5 cm². Find the central angle of the sector.

71.  Solve for x and y :

3x-2y = 4;  

x+y= 3

72. Find the distance of the point (6, -6) from the origin.

73. Prove that : (1 - sin²q) sec² q =1.

74. Find the length of canvas 1.1m wide required to build a conical tent of base radius 10.5 metres and height 14 metres.

75. The 7th term of an A.P. is 32 and its 13th term is 62. Find the A.P.

76.

77. Without plotting the graph of the polynomials find the vertex of the following polynomials (or parabola).

(i) f(x) = -4x² + 4x - 1

(ii) f(x) = 6x² - 7x - 3

(iii) f(x) = x² - 12x + 35

78. Find the term of the Arithmetic Progression 9, 12, 15, 18,.....which is 39 more than its 36th term.

79. Which term of the arithmetic progression 5, 15, 25,.... will be 130 more than its 31^st term?

80. Find the cubic polynomial having - 3, 2 and - 5 as its zeros.

81. Find the coordinates of middle point of A(x₁, y₁) and B(x₂, y₂)

82. The area of similar triangles ABC and DEF are 64cm² and 169cm² respectively. If the length of BC is 4cm, find the length of EF.

83. For what value of k, does the quadratic equation 9x² + 8kx +16 = 0 have equal roots?

84. In a musical chair game, the person playing the music has been advised to stop playing the music at any time within 2 minutes after she starts playing. What is the probability that the music will stop within the first half-minute after starting?

85. Use the method of Fundamental Theorem of Arithmetic to find the H.C.F. of 630, 945 and 1470

86. If sin θ= cos θ find the value of θ

87.

88. The 8th term of an Arithmetic Progression is -23 and its 12th term is -39. Find the A.P.

89. A bag contains 9 black and 12 white balls. One ball is drawn at random. What is the probability that the ball drawn is black ?

90. A wire when bent in the form of an equilateral triangle encloses an area of 121 Ö3 cm². The same wire is bent to form a circle. Find the area enclosed by the circle.

91. Show that the product of two irrational numbers is not necessarily irrational.

92. Find the ratio of the volume of a cube to that of a sphere which will fit inside the cube.

93. If one of the zeros of the quadratic polynomial f(x) = 3x² - 20x+ 3p + 4 is four times  the other, find the value of p

94. The wheels of a car are of diameter 80 cm each. How many complete revolutions does each wheel make in 10 minutes when the car is travelling at a speed of 66 km per hour?

95. The probability that it will rain tomorrow is 0.76. What is the probability that it will not rain tomorrow ?

96. Two candidates are to be selected from a group of 3 boys and 2 girls. Find the probability that

(i) one girl is selected

(ii) at least one girl is selected

97.

98. Find the [HCF x LCM] for 105 and 120.

99.

100. A dice is thrown once. Find

(i) p (an even number)

(ii) p (a number  ³ 3)

(iii) p (a number £ 4)

(iv) p (a number < 7)

(v) p (a number > 6)

(vi) p(an ace )

ANSWERS

1.

2. 6cm

3. x = 7,y =13.

4.

5.

6.

7.

8.

9. 49.5

10. 147.84 m²

11. 96.

12. (i) a = 4, d = -3              (ii) a = 3, d = 2

(iv) a = 0.7, d = 0.9

13. 264

14. x =7 or -1

15. 25th

16.

17. 1

18.       

19. 2,7,12,17,…..

20. 9th

21. (i) p ≠ 6

(ii) p ≠ -6

(iii) p ≠ 12

22. (i) 2, 5, 8, 11, 14

(ii) 10, 16, 22. 28, 34

(iii) 44, 40, 36, 32, 28

(iv) 7,0,-7,-14,-21

23.

24.

25. No

26. 6 cm

27. (-2,0)

28. 1,0

29. (i) It is an AP          (ii) It is an AP

(iii) It is not an AP   (iv) It is not an AP

(v)It is not an AP     (vi) It is not an AP

(vii)It is an AP

30.

31. 440 cm²

32. 3,5,7

33. 19404 cm³

34. (i) similar

(ii) similar

(iii) equilateral

(iv) equal, proportional

35.

36. 163

37.

38. 61.6 cm²

39. x³-10x²+11x+70.

40. 5.

41. 346.5 m², 3293.5 m²

42. 24.64 cm

43. 64

44. 9.625cm²

45.

46. 2:3

47. 7cm

48. 37,486

49.       

50.

51. (i) It is not a quadratic equation.

(ii) It is not a quadratic equation.

(iii) It is not a quadratic equation.

52. -21

53. 3

54.

55. (p = 3, q =2)

56.

57. (3,-2)

58.

59.

60.

61. 20k

62. 2926 m²

63. k=2.

64.

65. (3,2)

66.

67. 25 units

68.

69.

70. 72°

71. x=2,y=1

72.

73.

74. 525 m

75. 2,7,12,17……..

76.

77.     

        

78. 49th

79. 44th

80. x³+6x²-x-30.

81.

82. 6.5 cm

83. k = ±3

84.

85. 105.

86. 45°

87. 2.4 cm

88. 5,1,-1,-7……

89.

90. 346.5cm²

91.

92. 21 : 11

93.

94. 4375

95. 0.24

96.

97.

98. Given number are 150 and 120

HCF x LCM = Product of two numbers = 105 x 120 = 12600

99.

100.         

(iv) 1    (v) 0