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SUMMATIVE ASSESSMENT - I (2011)

Lakdfyr ijh{kk&I (2011)

SCIENCE / foKku

Class – X / & X

Time allowed : 3 hours Maximum Marks : 80 fu/kkZfjr le; % 3 ?k.Vs vf/kdre vad % 80

General Instructions : i). The question paper comprises of two sections, A and B. You are to attempt both the sections. ii). All questions are compulsory. iii). There is no overall choice. However, internal choice has been provided in all the five questions of

five marks category. Only one option in such questions is to be attempted. iv). All questions to section A and all questions of section B are to be attempted separately. v). Questions 1 to 4 in section A are one mark questions. These are to be answered in one word or

one sentence. vi). Questions 5 to 13 in section A are two marks questions. These are to be answered in about 30

words each. vii). Questions 14 to 22 in section A are three marks questions. These are to be answered in about 50

words each. viii). Questions 23 to 25 in section A are five marks questions. These are to be answered in about 70

words each. ix). Questions 26 to 41 in section B are multiple choice questions based on practical skills. Each

question is a one mark question. You are to select one most appropriate response out of the four provided to you.

lkekU; funsZ”k %

(i) bl iz”u i= dks nks Hkkxksa, Hkkx v vkSj Hkkx c esa ckaVk x;k gSA vkidks nksuksa Hkkxksa ds iz”uksa ds mRrj fy[kus gSaA

(ii) lHkh iz”u vfuok;Z gSaA

(iii) iwjs iz”u i= ij dksbZ p;u izkIr ugha gS ijUrq ikap&ikap vadks ds ikWap iz”uksa esa Hkhrjh p;u fn;k x;k gSA bu iz”uksa esa vki

dsoy ,d Hkhrjh p;u dks mRrj fy[kus ds fy, pqu ldrs gSaA

(iv) vkidks Hkkx v vkSj Hkkx c ds lHkh iz”uksa ds mRrj i`Fkd&iFkd fy[kus gksaxsA

(v) Hkkx v ds iz”u la[;k 1 ls 4 ds iz”u ,d&,d vad ds gSaaA buds mRrj ,d “kCn vFkok ,d okD; esa nsaA

(vi) Hkkx v ds iz”u la[;k 5 ls 13 ds iz”u nks&nks vadksa ds gSaA buds mRrj yxHkx 30&30 “kCnksa esa nsus gSaA

(vii) Hkkx v ds iz”u la[;k 14 ls 22 ds iz”u rhu&rhu vadksa ds gSaA buds mRrj yxHkx 50&50 “kCnksa esa nsus gSaA

(viii) Hkkx v ds iz”u la[;k 23 ls 25 ds iz”u ikap&ikap vadksa ds gSaA buds mRrj yxHkx 70 “kCnksa esa nsus gSaA (ix) Hkkx c ds iz”u la[;k 26 ls 41 ds iz”u iz;ksxkRed dkS”ky ij vk/kkfjr cgqfodYih iz”u gSaA izR;sd iz”u ,d vad dk gSA

fn, x;s pkj fodYiksa esa ls vkidks dsoy ,d lcls mi;qDr fodYi pquuk gSA

SECTION-A / ' '

1. Is burning of a candle wax a physical change or a chemical change ?

570033

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2. Why is carbon not used for reducing aluminium from aluminium oxide ?

3.

Mention any two limitations of using fossil fuels.

4. What is electric power ? State its SI unit.

SI

5. State the condition for the reaction of magnesium with water. Why do magnesium starts

floating when this reaction occur. State the products of the reaction.

6.

Crystals of a substance changed their colour on heating in a closed vessel but regained

it after sometime, when they were allowed to cool down.

(a) Name one such substance.

(b) Explain the phenomenon involved.

(a)

(b)

7. A white heavy metallic salt on heating makes a crackling noise and produces two gases one

of which is reddish brown and the residue left is yellow in colour. Identify the salt and write

the reaction involved.

8. What happens when sodium sulphate and barium chloride solutions are mixed

together ? Write reaction with observation.

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9.

Leakage of blood from vessels reduces the efficiency of pumping system. How is the

leakage prevented.

10. State any three characteristics of a good source of energy. Name the gaseous fuel which has

the highest calorific value.

11. The charge possessed by an electron is 1.6x10-19 coulombs. Find the number of electrons that

will flow per second to constitute a current of 1 ampere.

1.6109

12. Why does a current carrying conductor experiences a force when it is placed in a magnetic

field ? State Fleming’s left hand rule.

13. The wattage of a bulb is 24 W when it is connected to a 12V battery. Calculate its effective

wattage if it operates on a 6 V battery (Neglect the change in resistance due to unequal

heating of the filament in the two cases).

12 V 24 W

6V

14. Give one equation each for decomposition reactions where energy is supplied in the

form of :

(i) heat (ii) light (iii) electricity

(i) (ii) (iii)

15.

A sanitary worker uses a white chemical having strong smell of chlorine gas to disinfect the

water tank.

(a) Identify the chemical compound.

(b) Write its chemical formula.

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(c) Write chemical equation for preparing it.

(a)

(b)

(c)

16. The pH of the mouth of a person is lower than 5.5. What changes will occur in his mouth ?

How can these changes be controlled ? Write any two measures.

pH 5.5

17. Draw a lebelled diagram of a Neuron. List its Functions

18. Name the hormone synthesised at the shoot tips. How does it help the plant to response to

light ?

19. Name four gases commonly found in biogas. List two advantages of using biogas over fossil

fuels.

20. Name and state the law which relates the potential difference and the current flowing

through a conductor when the physical conditions are kept constant. Mention the shape of

the V-I graph in case of a conductor made of silver. Also state the physical quantity

represented by the slope of this graph.

V-I

21. An electric heater connected to a 220V line has two resistance coil of 22 ohms each. Calculate

the current if these coils are used :

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(a) separately (b) in series (c) in Parallel

22 220

(a) (b) (c)

22. (a) Describe an activity to draw the magnetic field line around a bar magnet.

(b) Give two characteristics of magnetic field lines.

(a)

(b)

23. (a) Define an Alloy.

(b) Write four important purposes of making alloy.

(c) Write the constituents of following alloys :

(i) Brass (ii) Bronze

(iii) Solder (iv) Stainless Steel.

(a)

(b)

(c)

(i) (ii) (iii) (iv)

OR (a) What is ‘corrosion’? Name the compound formed when :

(i) silver corrodes (ii) copper corrodes :

(b) Describe with an experiment the conditions essential for Rusting of iron.

(a)

(i) (ii)

(b)

24. (a) With the help of suitable diagrams explain the process of nutrition in amoeba.

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(b) How many times the blood goes through the heart during one cycle in

fish and why ?

(a)

(b)

OR (a) List the events that occur during photosynthesis.

(b) Name the respiratory pigment present in our body ? Where is it present ?

(c) Why are valves present in heart and veins ?

(a)

(b)

(c)

25. What is a solenoid ? Draw the patterns of magnetic field lines of a solenoid through

which a steady current flows ? What does the pattern of field lines inside the solenoid

indicate ? Write one use of solenoid.

OR (a) State the rule to determine the direction of a

(i) Magnetic field produced around a straight conductor carrying current

(ii) Force experienced by current - carrying straight conductor placed in a

magnetic field which in perpendicular to it.

(iii) Current induced in a coil due to its rotation in a magnetic field.

(b) Differentiate between AC and DC. Write one advantage of AC over DC

(a)

(i)

(ii)

(iii)

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(b) AC DC

SECTION –B / ' '

26. The correct method of finding the pH of a solution is to :

(a) heat the solution in a test tube and expose the pH paper to the vapours formed.

(b) pour the solution on the pH paper.

(c) dip the pH paper in the solution.

(d) put a drop of the solution on the pH paper using a dropper.

pH

(a) pH

(b) pH

(c) pH

(d) pH

27. Wher student dipped pH paper in the given solution, he found green colour. The given

solution may be

(a) NaOH solution (b) NaCl solution

(c) dilute HCl (d) Na2 CO3 solution

pH

(a) NaOH (b) NaCl

(c) HCl (d) Na2 CO3

28. When drops of blue litmus solutions are added to dil. HCI and aqueous NaOH taken in

two different test tubes A and B respectively, what will be the colour changes

occurring?

(a) blue to red in both A and B.

(b) no change in both A and B.

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(c) blue to red in A and no change in B.

(d) blue to red in B and no change in A.

A B HCl NaOH

(a) A B

(b) A B

(c) A B

(d) B A

29. Rahul adds aqueous solution of barium chloride to an aqueous solution of sodium sulphate.

He would observe that

(a) a pungent smelling gas is evolved.

(b) the colour of the solution turns red.

(c) a yellow precipitate is formed after sometime.

(d) a white precipitate is formed almost immediately.

(a)

(b)

(c)

(d)

30. If iron nails are kept in CuSO4 solution for two hours, the colour of the solution will

change in to :

(a) Pink (b) Red

(c) Light green (d) Yellow

2 CuSO4

(a) (b)

(c) (d)

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31.

The normal positions of pointers if two ammeters and two voltmetres are shown. For

verification of Ohm’s law the student should select :

(a) ammeter A1 and voltmeter V1 (b) ammeter A2 and voltmeter V1

(c) ammeter A1 and voltmeter V2 (d) ammeter A2 and voltmeter V2

(a) A1 V1 (b) A2 V1

(c) A1 V2 (d) A2 V2

32. While performing the experiment on studying the dependence of current (I) on the potential

difference (V) across a resistor, four student I, II, III and IV set up the circuit as shown.

The correct result will be obtained by the student.

(a) I (b) II (c) III (d) IV

(V) (I)

I, II, III IV

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(a) I (b) II (c) III (d) IV

33. The voltmeter, ammeter and resistance in the circuit shown have been checked to be correct.

On plugging the key, the ammeter reads 0.9A but the voltmeter reads zero. This could be

because :

(a) The range of the voltmeter is more than twice the battery voltage

(b) The least count of the voltmeter is too high

(c) The wires joined to the voltmeter terminals are loose.

(d) The voltmeter is incorrectly placed in the circuit

0.9A

(a)

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(b)

(c)

(d)

34. The following ammeters and voltmeters are available in the laboratory to find

equivalent resistance of two resistors R1 and R2 in parallel

Ammeters : A1 of Range 0 to 300mA : Least Count 10mA

A2 of Range 0 to 100mA : Least Count 20mA

Voltmeters : V1 of Range 0 to 5V : Least Count 0.2 V

V2 of Range 0 to 4V : Least Count 0.4 V

The best combination of voltmeter and ammeter would be

(a) ammeter A1 and voltmeter V1

(b) ammeter A1 and voltmeter V2

(c) ammeter A2 and voltmeter V1

(d) ammeter A2 and voltmeter V2

R1 R2

A1 0 300mA ; 10mA

A2 0 100mA ; 20mA

V1 0 5V ; 0.2 V

V2 0 4V ; 0.4 V

(a) A1 V1

(b) A1 V2

(c) A2 V1

(d) A2 V2

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35. Two students (A) and (B) connect their two given resistors R1 and R2 in the manners shown

below.

Student A connects the terminals marked b1 and c1 while student B connects the terminals

marked d2 and c2 in their respective circuits at the points marked X and Y.

Which one of the following is correct in relation to above arrangement

(a) both the students will determine the equivalent resistance of the series combination of

the two resistors

(b) both the students will determine the equivalent resistance of the parallel combination of

the two resistors

(c) Student A will determine the equivalent resistance of series combination while student

B will determine the equivalent resistance of parallel combination of the two resistors

(d) Student A will determine the equivalent resistance of the parallel combination while

student B will determine the equivalent resistance of the series combination of the two

resistors.

(A) (B) R1 R

2

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A b1 C

1 Y B d

2 C

2 X Y

(a)

(b)

(c) A B

(d) A B

36. Steps involved to test the presence of starch in a leaf are shown by figure (i), (ii), (iii) and (iv)

which are not in correct sequence ? Which one of the following is the correct sequence for the

process to test the starch ?

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(a) (i), (iii), (ii) and (iv) (b) (i), (ii), (iv) and (iii)

(c) (i), (iv), (iii) and (ii) (d) (ii), (iii), (i) and (iv)

(i), (ii), (iii) (iv),

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(a) (i), (iii), (ii) (iv) (b) (i), (ii), (iv) (iii)

(c) (i), (iv), (iii) (ii) (d) (ii), (iii), (i) (iv)

37. A leaf of destarched plant was covered with black paper strips on both sides and then

exposed to sunlight for 3 - 4 hours. The leaf was then plucked, boiled in Alcohol and

tested with iodine solution. The uncovered part of the leaf turned blue black. The

inference is that

(a) water is necessary for photosynthesis.

(b) light is necessary for photosynthesis.

(c) CO2 is necessary for photosynthesis.

(d) starch is necessary for photosynthesis.

3 - 4

(a) (b)

(c) CO2 (d)

38. While preparing a temporary stained mount of a leaf epidermal peel, the extra stain is

removed by :

(a) washing with water

(b) washing with calcium chloride

(c) soaking with filter paper

(d) absorbing with cotton wool

(a)

(b)

(c)

(d)

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39. A student focused the leaf epidermal peel under a low power microscope, but he could not

see all the parts. He should :

(a) use the coarse adjustment knob again to focus the slide

(b) use the fine adjustment knob to increase magnification

(c) focus under high power using coarse adjustment knob

(d) focus under high power using fine adjustment knob

(a)

(b)

(c)

(d)

40. In the experiment demonstrating respiration in germinating seeds, the water rises in the

delivery tube due to

(a) seeds use up oxygen in the flask.

(b) CO2 is given out by germinating seeds.

(c) germinating seeds suck the water from the beaker.

(d) a partial vacuum is created as CO2 is absorbed by KOH.

(a)

(b) CO2

(c)

(d) KOH CO2

41. In the experimental set up to show that CO2 is given out during respiration KOH is kept in

the conical flask to

(a) create partial vacuum in the flask. (b) absorb moisture in the flask.

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(c) provide O2 to the germinating seeds. (d) keep the flask air tight.

CO2 KOH

(a) (b)

(c) O2 (d)