Solved question paper for Science Mar-2016 (UBSE 10TH)

Question paper 1

1. 1. Four option are given in each part of question write the correct answer in your answer book
   (a) Which of the following is an amphoteric oxide

   
    

   (i)

   Na2O

   (ii)

   Al2O3

   (iii)

   MgO

   (iv)

   SO2

   Answer:

   (ii)

   Al2O3

2. (b) The process by which the black coating on silver and green coating on copper occurs known as

   
    

   (i)

   Neutralization

   (ii)

   oxidation

   (iii)

   reduction

   (iv)

   corrosion

   
    

   Answer:

   (iv)

   corrosion

3. (c) Lamp the associated with which part of human system
    

   (i)

   Acceleration

   (ii)

   transportation

   (iii)

   nutrition

   (iv)

   Respiration

   Answer:

   (ii)	transportation

4.  (d) The symbol used to represent a plug key or switch open in an electric current is

   (i)

   (ii)

   (iii)

   (iv)

   
    

   Answer:

   (iii)

6. (e)The human eye from the image of an object at its

   (i)

   Cornea

   (ii)

   Iris

   (iii)

   Pupil

   (iv)

   retina

   Answer:

   (iv)

   retina

7.  (f)Biodiversity hot spots are

   (i)

   Fields

   (ii)

   forest

   (iii)

   Garden

   (iv)

   polar region

   
    

   Answer:

   (ii)

   forest

8. 2. Name the main constitution of base

   Answer:

   Copper + Zink =Brass (Cu+Zn)= Brass

9. 3. Write full form of HIV

   Answer:

   HIV is equal to human immunodeficiency virus

11. 4. in which direction a freely suspended bar magnet rest 

    Answer:

    North south direction

12. 5.what is the focal length of a plane mirror

    Answer:

    the focal length of a plane mirror is infinity.

13. 6. write name of two alternate source of energy 

    Answer:

    Solar energy and wind energy

14. 7. balance the following chemical equation 

    (a) NaOH+H₂SO₄ Na₂SO₄+H₂O

    (b) Fe + H₂O Fe₃O₄ + H₂

    Answer:

    (a) 2NaOH + H₂SO₄ Na₂SO₄ + 2H₂O

    (b) 3Fe + 4H₂O Fe₃O₄ + 4H₂

16. 8. name the following compounds 

     

    Answer:

    (a) Propanol

    (b) Ethanoic acid

17. 9.write the name of tissues
    (a) which transport food in plant

    Answer:

    Phloem

18. (b) which transport water and mineral in plants 

    Answer:

    Xylem

19. 10.what are fossils? how fossils provide evidence for evaluation?

    Answer:

21. 11. what advantage over an aquatic organism does a a terrestrial organism have with regard to obtaining oxygen for respiration?

    Answer:

22. 12. 25 coulomb of charge flow through a conductor in 10 second calculate the current flow through the conductor.

    Answer:

    Given q=25C

    t=10 sec

    we know that I=q/t

    I =25/10

    I=2.5 Ans

23. 13. how can three resistor of resistance  2Ω 3 Ω and 6 Ω be connected to give a total resistance of 4 Ω  two lenses of power

    Answer:

    R₁ = 3 Ω

    R₂ = 6 Ω

    R₃ = 2 Ω

    R₁ & R₂ are connected in parallel

     

     

     

     

    Now the Rebultant resistance is

     

     

24. 14.  2.5 D and 1.5 D are place in contact with each other what will the power of combination 

    Answer:

    Given Power of first lens (P₁)= + 2.5 D

    Power of first lens (P₂)=+ 1.5 D

    the power of combination

    P= P₁+ P₂

    P= + 2.5 + 1.5 D

    P= +4D

26. 15. what is meant by producer and consumer?

    Answer:

    Producer:- producer are organism which can prepare their own food from simple organic substance like carbon dioxide and heat by using sunlight energy in the presence of chlorophyll

    consumers:- all those organism which consume food prepared by producers are called consumer all animals are consumers.

27. 16. Give the electronic dot structure of following.

    Answer:

28. 17. (a)write chemical formula of hydrated  copper sulphate 

     

    Answer:

    hydrated copper sulphate – CuSO₄.5H₂O

29. (b)what is the chemical name of plaster of Paris give chemical equation involved in the preparation of plaster of paris 

    ​

    Answer:

31. 18. what happen when (Give chemical equation only)
    (a) Carbon dioxide gas is passed through lime water 

    Answer:

    (a)

32. (b) Sodium hydrogen carbonate is strongly heated 
    (c) Bleaching powder react with dilute hydrochloric acid 

    Answer:

    (b)

    (c)

33. Or
    compare any contrast the arrangement of element in Mendeleev’s periodic table and Modern Periodic Table 

    Answer:

    	Mendeleev’ periodic table	The Modern periodic table
    1.	Element arrange in the increasing order of their atomic mass	Element are arranged in increasing order their atomic number
    2.	There are total 7 groups and 6 periods	There are total 18 groups and 7 periods
    3.	The position of hydrogen could not be explained	Hydrogen is placed above alkali metal
    4.	Element having similar properties where placed directly under one another	Element having same valence shell are present in the same period while element having the same number of valence electrons are present in the same group
    5.	Load distingushing position are metal and nonmetal	Metals are present in the left hand of the the p.t where as non metal are present at the right hand side

34. 19. How is Oxygen and Carbon dioxide transport in human being explain 

    Answer:

    Human beings oxygen is carried from the lungs by respiratory pigment hemoglobin which is present in red blood Core Plus hemoglobin has a very high end of oxygen carbon Dioxide more soluble in water than oxygen so most of the carbon dioxide produced during respiration in the human body is transported in the dissolved from in our blood.

36. 20. What are the components of transport system in human being what are the function of these components

    Answer:

    The component of transport system in human beings are blood and PH the function of blood and mph are as follow

    (1) red blood cells carry oxygen from the lungs to all the cells for the blood blood plasma carried digest food protein common salt tasty products and hormones from one part to another part in the body

    (2) lymph put into circulation large protein molecules by carrying them from the tissue into the blood steam lymph also carry digested from intestine to another tissue and exercise fluid from the extra circular space back into blood.

37. 21.  Write short note on following 
    (a) artificial kidney (hemodialysis )
    (b)regeneration 

    Answer:

    (a) Artificial kidney an artificial kidney is a device to remove auto genius has reproductive from the blood through dialysis

    (b) Regeneration:- regeneration is ability to repair and Jerry part and replace the once lost tissue by degeneration of new tissue regeneration is ability to grow the last part from the parent body.

38. 22. (a) What is meant by electrical resistivity e of the material of conductor? classify 

    Answer:

39.  (b) Why is tungsten metal selected for making filament of an electric bulb 

    Answer:

41. 23. What is long sightedness? List two cause  of development of long sightedness. Describe with the ray diagram how this defeat may be corrected by using speculates.

     

    Answer:

42. Or
    An object 5 cm in length is placed perpendicular to the principal axis of convex lens of focal length 20cm the distance of object from lens is 30 cm find  (i) Position  (ii) Nature  (iii) Size of image formed by it 

    Answer:

    Given

    Height of object H=5cm

    f=20cm

    U=-30cm

    But we know that

     

     

     

     

     

    (a)

     

     

     

    (i) Position =behind the mirror

    (ii) Nature = virtual and crect

    (iii) Size of image = 2cm

43. 24. (a) What is acid rain write one harmful effect of acid rain 

    Answer:

    Acid rain is rain that unusually acidic and consumer in nature it is rain with the high level of hydrogen ions it may be defined as rain water having pH less than 5.6 acid rain can harmful effect on plant animal and humans in acid rain Sulphur dioxide and Nitrogen dioxide do damage human health

44. (b) What is food chain

    Answer:

    Food chain:- Food chain is a linear network of links in food hubs starting from producer organism and ends at Apex product or species deritivors all D composer species cg.net composed organism that cat auto herm the organisms are called primary consumer

46. Or
    What is meant by rainwater harvesting mention some of the common method used of rainwater harvesting by the ruler people? 

    Answer:

    Rainwater harvesting is a technique of collection and storage of rainwater into natural reservoirs or thanks for the infiltration of surface water into substance aquifers

    Rooftop rainwater harvesting:- in this people called the rainwater from the roof in the big container as the first supplies of the rain is not correct because it is usually the roof and other rain sure are collected in containers

    Underground tanks :-in rular area people build underground tank and collect the rain water in data through pipe pipes are connected with roof through which the water is collected.

47. 25. How will you obtain give chemical equation only 
    (a) Ethanol acid of Ester                          (b) sodium ethnocide from Ethyl alcohol
    (c) Methyl chloride from methane       (d) sodium acetate from ethanol acid 

    Answer:

    (a)

    (b)

    (c)

    (d)

48. 26. Differentiate in following 
    (a) Oxidizing agent and reducing agent 

    Answer:

49. (b) Mineral and ore

    Answer:

51. Or
    Oxygen (atomic number 8) and Sulphur (atomic number 16) belong to group 16 of the product table write electronic configuration of these two element which of these element will be more electronegative and why 

    Answer:

    Oxygen (atomic number 8)

    E.C: 2,6

    Sulphur (atomic number 16)

    E.C: 2,8,6
     

52. 27. (a) What are endocrine gland? Write the name of two endocrine gland found in human body

    Answer:

    Endocrine gland:-

    Endocrine gland in human body:- (1) Hypothalamus (2) pituitary gland

53. (b) What is the difference between Asexual and sexual reproduction 

    Answer:

54. Or
    (a) Draw labelled diagram of human female reproductive system 

    Answer:

56. (b) How sex of a child is determined in human being 

     

    Answer:

57. 28. (a)  In the given circuit diagram calculate-              diagram
    (i) Total resistance in arm CD 
    (ii) Total current drawn from battery

    Answer:

58.  (b) What are the advantages of connecting electrical devices in parallel with the battery instead of connecting them in series 

    Answer:

59. Or 
    (a) A torch bulb is rated 5v and 500 m a calculate 
    (i) Power of bulb
    (ii) Resistance of bulb 
    (iii) Energy consumed by bulb  when it is lighted for 4 hours 

    Answer:

    Given

     

     

    (i) Power of bulb

     

     

     

    (ii) Resistance of bulb

     

     

     

     

     

    (iii)

     

     

     

     

     

     

61. (b) What determines the rate at which energy is delivered by a current ?

    Answer:

    The rate of which energy is delivered by a current is power of the appliances

62. 29. (i) what is the least distance of distinct vision of normal human eye 

     

    Answer:

    The minimum distance of an object from eye to have its clear image is called least distance of distant vision the distance is about 25 cm from the eye

    (ii) the magnification produced by plane mirror is + 1 what does it mean explain

63. (ii) the magnification produced by plane mirror is + 1 what does it mean explain

     

    Answer:

    The magnification of mirror is + 1 means the distance of the object is same as the distance of the image and the height of image is a same as the height of object

64. (iii) why do start twinkle?

    Answer:

    Twinkling of star is due to the atmosphere reflection of stars light light reaching our eyes changing continuously due to atmospheric reflection it undergoes wearing optical density of air and various attitude there for the stars appear twinkling at night.

66. 30 (i)what are the characteristic of good fuel?

     

    Answer:

    Characteristics of good fuel

    1. It should be economical

    2. It should be easy to store and transport

    3. It should be easily available and accessible

    4. It should be process flow irrigation temperature

67. (ii) Compare and contrast Biomass and hydroelectricity as source of energy?

    Answer:

    	Biomass	Hydroelectricity
    1.	it is a renewable source of energy	It is a non renewable resources of energy
    2.	It produces chemical energy	It produces kinetic energy of a running water at high altitudes
    3.	It causes air pollution	It does not causes air pollution
    4.	Biomass is relatively more economical source of energy	It is costly as compared to Biomass