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## Saturday, March 29, 2014

### CBSE Test papers for Ch. Rational number Class 8

Rational Numbers test paper for class 08 Mathematics. These test papers include all main concepts of the chapter in CBSE class 08 Mathematics. It is very useful for testing and commanding over the topic and to excel in various Olympiads and other competitions

 Introduction
 Properties of Rational Numbers
 Representation of Rational Numbers on the Number line.
 Rational Numbers between two rational numbers.
Learning Objectives:
 The students learn to represent rational numbers on the number line. They learn to verify various properties taking different values.

8th maths Rational Number CBSE Test Paper - 01
8th maths Rational Number CBSE Test Paper - 02
8th maths Rational Number CBSE Test Paper - 03
8th maths Rational Number CBSE Test Paper - 04
8th maths Rational Number CBSE Test Paper - 05

8th maths Rational Number CBSE Worksheet - 01
8th maths Rational Number CBSE Worksheet - 02
8th maths Rational Number CBSE Worksheet - 03
8th maths Rational Number CBSE Worksheet- 04

## Sunday, March 16, 2014

### CBSE-XII-2014 PHYSICS Code : 56/3 and CHEMISTRY Code : 55/3 Solution

CHEMISTRY  Paper & Solution Code : 55/3
Time : 3 Hrs. Max. Marks : 70

General Instructions :

(i) All questions are compulsory.
(ii) Questions number 1 to 8 are very short answer questions and carry 1 mark each.
(iii) Questions 9 to 18 are short answer questions and carry 2 marks each.
(iv) Question number 19 to 27 are also short-answer questions and carry 3 marks each. ) Question number 28 to 30 are long-answer questions and carry 5 marks each.
(vi) Use Log Tables, if necessary. Use of calculators is not allowed

Physics Paper & SolutionCode : 55/3

Time : 3 Hrs. Max. Marks : 70

General Instruction :

(i) All questions are compulsory.
(ii) There are 30 questions in total. Questions 1 to 8 are very short answer type questions and carry one mark
each.
(iii) Questions 9 to 18 carry two marks each, questions 19 to 27 carry three marks each and questions 28 to 30 carry five marks each.
(iv) One of the questions carrying three marks weightage is value based question
(v) There is not overall choice. However, an internal choice has been provided in one question of two marks, one question of three marks and all three question of five marks each weightage. You have to attempt only one of the choices in such questions.

English Paper & Solution Code : 1/2

Time : 3 Hours M.M. 100

General Instruction :

(i) This paper is divided into three sections : A, B and C. All the sections are compulsory.
(ii) Separate instructions are given with each section and question, wherever necessary. Read these instructions very carefully and follow them faithfully.
(iii) Do not exceed the prescribed word limit while answering the questions

Solution Board Examinations 2013 Class-XII English (Core)

### IX Sanskrit and Hindi Original Question Paper New Term-2

X Hindi Original Paper with OTBA 2014-1

IX Hindi Original Paper with OTBA 2014-2

IX Hindi Original Paper with OTBA 2014-3

IX Hindi Original Paper with OTBA 2014-4

IX Sanskrit Original Paper with OTBA 2014-1

IX Sanskrit Original Paper with OTBA 2014-2

## Friday, March 14, 2014

### CBSE Class 9 Sample Paper SA-1 Sep 2014

IX Maths Sample Question paper SA-1 for 2014-2015-1

SA-1 Class IX Maths Sample paper 2014-15-2

SA 1 Class IX Science Sample Question paper 2014-15

SA 1 Class IX Social Science Sample Question paper 2014-15

SA 1 Sample paper Class IX Hindi 2014-15

SA 1 Sample paper Class IX English 2014-15

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## Wednesday, March 12, 2014

### IX Original Paper with OTBA for 2014 CBSE Board

IX Maths Original Paper with OTBA 2014
IX Science Original Paper with OTBA 2014
IX Social Science Original  Paper with OTBA 2014
IX Hindi Original  Paper with OTBA 2014
IX English Original  Paper with OTBA 2014

## Tuesday, March 11, 2014

### Solved 10th Science Board Paper - 2014 code 31/2

1. Atomic no. of x = 12; Atomic No. of y = 16

2. The transfer of traits from parents to offspring is called heredity.

3. Paper and glass can be easily recycled but thrown in the dust bin.

4. This is because both the father and the mother contribute practically equal amounts of genetic material to the child during sexual reproduction in forming ztgote.

5. Object placed between pole and focus see in diagram:

6. Decomposer break-down the complex organic substances into simple inorganic substances. The natural replenishment of the soil also takes place by Decompose.

7. Watershed management is the study of the characteristics of a watershed. It helps to manage water quality, water supply, and drainage and rainwater flow. It also ensures sustainable maintenance planning of a watershed.

Benefits of a watershed management system:

Water quality is strictly maintained.

Distribution of water is equal and sustainable.

8. The producers convert solar energy into chemical energy in the form of organic compounds. The primary consumers (herbivores) derive their nutrition from the producers. According to the energy transfer law, only 10% of energy is transferred from one trophic level to the other. So, the energy that is captured by the producers does not revert back to the Sun and the energy transferred to the herbivores does not come back to the producers. It just keeps on moving to the next trophic level in a unidirectional way. That is why the flow of energy in the food chain is always unidirectional.

A large number of pesticides and chemicals are used to protect our crops from pests and diseases. Some of these chemicals are washed down from the soil, while some enter the water bodies. From the soil, they are absorbed by plants along with water and minerals; and from the water bodies, they are taken up by aquatic plants and animals. This is how these chemicals enter the food chain. As these chemicals cannot decompose, they accumulate progressively at each trophic level. This increase in the concentration of harmful chemicals with each step of the food chain is called biomagnification. As human beings occupy the top level in any food chain, these chemicals get accumulated in our bodies.

10. (a) He should use a concave mirror, as it forms a real image on the same side of the mirror.
(b) Object distance, u = -12 cm
image distance, v = - 48 cm
Magnification, m = -vu = -(-48)(-12) = -4
The minus sign in magnification shows that the image formed is real and inverted.
(c) The image is formed at a distance of 36 cm from the object.
(d) In this case, the image is formed beyond the centre of curvature. This image is real, inverted and enlarged.

11. (i) The phenomena of the splitting of the white light into its constituents colours is called dispersion of the light. Therefore, the phenomena observed is dispersion of light.

The dispersion of light is caused, because different constituent colours of light offers different refractive index to the material of the prism.

(ii) The formation of rainbow is caused by the dispersion of white sunlight into its constituents colours.

(iii) Based on the dispersion of white light into its constituent colours we conclude that:

(a) White light consists of seven colours.

(b) The violet light suffers the maximum deviation and red light suffers the minimum deviation

12. Given:
C2H4O2 + RCH2OH →H+X

RCH2OH →H+KMnO4 C2H4O2

Chemical reactions involved:

CH3COOH + C2H5OH → H+ CH3COOC2H5 C2H4O2 Alcohol X C2H5OH →H+KMnO4 CH3COOHAlcohol

(i) The carboxylic acid involved in the reaction is acetic acid (CH3COOH).
(ii) The alcohol involved in the reaction is ethanol (CH3CH2OH).
(iii) X is the ester formed by the condensation of acetic acid, and ethanol is ethyl acetate (CH3COOC2H5)
MCQS
25. (C) Convex lens of focal length 20 cm.

26. (B) Concave and F1 > F2

27. (D) 2, 3 and 4

28. (C) 20 cm on the other side of the lens and is of the same size, real and inverted.

29. (D) Y, Q and P

30. (B) Q

31. (C) ∠r only

32. (C) III

35. (C) III and IV

36. (C) III, II, I, IV

37. (B) II, I, IV, III

38. (A) 2, 3 and 5

39. (D) I, II and IV

40. (B) the ethanoic acid dissolves readily in water.

41. (C) White pellets/flakes

42. (A) the reaction is exothermic and the reaction mixture is acidic.

### Class IX original Board paper Science Summative -2 for 2013-14[code-7RL2FCZ]

Time: 3-3and1/2 hr _ Max mark: 100 [includes 10 marks based on Open Text Theme]

Test held in School:
Sadhana Devi Vidyapith, Samastipur - Punjabi Colony [By JSunil]

1 mark

1. As per the law of definite proportional carbon and oxygen combine in ratio 3: 8. Compute the mass of oxygen gas that would be required to react completely with 6 gm carbon.

2. A pore bearing organism like creature “A” belong to a phylum “B” of kingdom Animalia.

3. In which reason is soil erosion very difficult to revert.

2 marks

4. Explain, What is Organ specific manifestation?

5. A man drops a stone of mass 2 kg room the top of a building of height 15m when it reaches the ground, find its kinetic energy.

6. When an object is immersed in the fluid name the two forces acting on it.

3 marks

7. (a) The mass number of an element is 18. It contains 7 electrons. What is the number of proton? and neutron in it.

(b) State the problem of atomic structure which was solved after the discovery of neutron.

8.(a)From Rutherford a - particle scattering experiment give the experimental evidence for deriving the conclusion that

(i) Most of the space inside the atom is empty

(ii) The nucleus of atom is positively charged

(b)An element has mass number 31 and atomic number 15 find

(i) The number of neutron in element

(ii) The number of electron in element

9. Write three point of difference between an atom and molecules

10. Carolus Liniaus gave the two kingdom of classification. Latter it was changed by Ernst Haikel (1894) and in 1959 , ,Whittaker gave the five kingdom classification. Do you think that studying about the work done by earlier scientists or their obsolete theories is useful for student of this generation? Give three reasons.

11.What are phanerogams? Name its two groups along with the criteria of division.

12.A man has an audible range from 20Hz to 20kHz. What are the wave lengths of sound in air corresponding to these two frequencies? (Speed of sound is 344m/s)

13.How does the sound produced by a musical instrument , reach your ears? Astronauts need radio telescope to talk to each other on moon why?

14. (A) Name the type of energy posses by moving object?
(b) Derive the expression for this energy for an object moving with velocity v and having mass m
15.(a)Define frequency and amplitude. (b)Draw diagram to represent (i) soft sound (ii) Loud sound
16. A solid weight 75g in air and 55.6 g in water. Find the relative density of the solid. Also state if the object will float or sink when immersed in water.
17. How are cloud formed and what bring us rain.
18. Mention any three important roles of water essential for life of organism on the earth’s surface.
5 marks
19.(a)Write chemical formula of all compounds that can be formed by the combination of following ions: Ca2+ , K+ , Fe3+ , Cl-, SO42-
(b)Molar mass of nitrogen is 14u. What will be the mass of one atom of nitrogen in gram?
20. Fill in the blanks
 Disease microbes Target organ Mode of transmission Meningitis virus -----(a)--------- Fecal contamination Hepatitis ---(b)------ ---(c)------- Contamination water ---(d)----- Bacteria Lungs ----(e)------------ Ringworm fungus ---(f)------- Indirect Contact ---(g)------- Virus Lungs -----(h)----------- Dengue fever -----(i)----- Whole body ----(j)-----------

21.(a)What kind of food is advised when we fall sick and why
(b)Mention any three basic conditions required for good health.

22. Define frequency and wavelength with reference to sound. Explain what is echo . Write full form of SONAR. Give two application of Ultrasound.

23. (a) Define 1Kwh.
(b) How is the power related to the speed at which an object is lifted?
(c) if an electric iron of 1600W is used for 45 min every day , find the electric energy consumed in month of march.

24. What is meant by depletion of Ozone layer? Mention one important feature of ozone in atmosphere. Identify the factor responsible for creation of ozone hole?
Visit to get more original paper
IX Maths Original Sample Paper with OTBA 2014
IX Science Original Sample Paper with OTBA 2014

IX Social Science Original Sample Paper with OTBA 2014

## Sunday, March 9, 2014

### IX class Guess questions on Mole concept[Atoms and Molecules]

Q. Find the gram molecular mass of water (H2O)
Calculation: 2(H) = 2 x 1 = 2 . 1(O) = 1 x 16 = 16
∴ Gram molecular mass of H2O= 18g

Mole is defined as the amount of substance that contains as many specified elementary particles as the number of atoms in 12g of carbon-12 isotope.

One mole is also defined as the amount of substance which contains Avogadro number (6.023 x 10^23) of particles.

For eg. one mole of oxygen atoms represents 6.023 x 10^23 atoms of oxygen and 5 moles of oxygen atoms contain 5 x 6 . 0 2 3 x 10 ^23 a t oms of oxygen .

Q. Calculate the number of aluminium ions present in 0.051 g of aluminium oxide. [Hint : The mass of an ion is same as that of an atom of the same element.

Sol: 1 mole of Al2O3 contains aluminium ions = 2 × 6.022 × 10^23 = 12.044 × 10^23

Now, 102 g of Al2O3 has number of aluminium ions = 12.044 × 10^23

0.051 g of Al2O3 has number of aluminium ions = (12.044 ×1023 × 0.051)/102= 6.022 × 10^20 ions

Q. How many atoms of oxygen are present in 50g of CaCO3? [Ca = 40, C = 12, O = 16]

Sol: 100 g of CaCO3 contains = 3 × 6.022 × 10^23 atoms of oxygen

50 g CaCO3 will contain = (3 × 6.022 × 10^23 × 50)/100 = 9.033 × 10^23 atoms of oxygen

Q. What is the concentration of hydrogen ions in 1 mol/dm3 of sulphuric acid?

Ans. H2SO4 → 2H+ + SO42–

1 mole of sulphuric acid (H2SO4) contains = 2 g of hydrogen ions.

∴ Concentration of hydrogen ions in 1 mole of sulphuric acid = 2 g/dm3 of hydrogen ions.

Q. What happens to an element 'Z' if its atom gains three electrons?

Ans. It forms Z3– ion. Z + 3e– → Z3–

Q. Calculate the mass of 1 molecule of oxygen. [Given atomic mass of hydrogen = 1 u and oxygen 16 u]

Ans. 6.022 × 10^23 atoms of oxygen weigh = 16 g

1 atom of oxygen will weigh = 16/6.022 ×10^23g = 2.66 × ^10–23 g

Q: (a) Calculate the number of molecules in 8 g of O2.

(b) Calculate the number of moles in 52 grams of He (Helium).

Sol: (a)32 g of O2 contains 6.022 ×10^23 molecules

8 g of O2 contains 6.022 ×10^23 molecules x(8/32)= 1.5055 × 10^23 molecules

(b) Molecular mass of He = 4 g,

4 g of He = 1 mole

52 g of He =(1/4) × 52 = 13 mole

Q. Magnesium and oxygen combine in the ratio of 3 : 2 by mass to form magnesium oxide. How much oxygen is required to react completely with 12 g of magnesium?

Ans. According to the law of constant proportion "In a pure substance same elements are always present in a definite proportion by weight".

3 g of magnesium reacts with oxygen = 2 g

12 g of magnesium reacts with oxygen = 12 × (2/3) = 8 g

Sol: Atomic mass of NH3 = 14 + 3 × 1 = 17

17 g of NH3 atoms = 1 mole

34 gm of NH3 atoms = 34x(1/17) = 2 mole

Q. Calculate the number of moles of the following :

(a) 84 g of nitrogen atom (b) 8.066 × 10^23 number of nitrogen atom (given atomic mass of N = 14)

Ans. (a) 14 g of nitrogen atoms = 1 mole

84 g of nitrogen atom = [1/14] 84 = 6 moles

(b) 6.022 × 10^23 of nitrogen atoms = 1 mole

∴ 8.066 × 10^23 nitrogen atoms = (1/6.022 × 10^23) x 8.066 × 10^23 = 1.339 moles

Q. A sample of vitamin C is known to contain 2.58 × 1024 oxygen atoms. How many moles of oxygen atoms are present in the sample?

Sol: 6.022 × 10^23 of oxygen atoms = 1 mole

Number of oxygen atoms in the sample of vitamin C = 2.58 × 10^24 /6.022 × 10^23 = 4.28 mol in the sample

Q. What is the mass of 0.5 mole of NH3 ? Given Atomic mass of N = 14u, Atomic mass of H = 1u.

Sol: 17 x 0.5 = 8.5g

Q. Calculate the number of particles in 31 g of P4 molecules. Atomic mass of P=31u.

Sol: 1.5x10^23

Q Find the number of moles in 87g of K2SO4 (Atomic mass of K=39u, S=32u, O=16u)

Sol: 0.5 mole

Q. Calculate the number of moles for the following.

(i) 36g of He (At. Mass of He =4 u) (ii) 12.044x10^23 molecules of H2O (At. mass of He=1 u, O= 16 u)

## Friday, March 7, 2014

### 12th class Physics Exam 2014 rescheduled in Manipur

 Credit: http://www.thehindu.com/
Two days after an Imphal based newspaper (Hueiyen Lanpao) carried a report of leaking three sets of Physics question papers of the ongoing All India Senior Secondary Certificate Examination (AISSCE) 2014 conducted by Central Board of Secondary Education (CBSE), the CBSE is all set to conduct re-examination of Physics in all the examination centres in Manipur on April 2 this year.

“Due to administrative reasons, it has been decided to cancel the examination in Physics for AISSCE 2014 held in the centres situated in the state of Manipur”, says CBSE’s Controller of Examination MC Sharma in a notification on Friday. “It has been decided to conduct re-examination of Physics in respect of all centres of Manipur.”

The re-examination of Physics would be held on Wednesday (April 2) from 10.30am to 1.30pm.

The said “leaked out” question papers were sold for Rs. 3,000 to Rs. 5,000 prior to its examination day (March 5) in Manipur, reports Hueiyen Lanpao.

But the state government remained silent untill the Democratic Students' Alliance of Manipur came out with a statement demanding to cancel the physics paper examination and announce it as invalidated.

Manipur’s Education minister Moirangthem Okendra convened a meeting of the state educanists including the key functionaries of the Board of Secondary Education Manipur and Council of Higher Secondary Education Manipur on Thursday and discussed to formulate a monitoring policy for the CBSE affiliated schools in the state.

Expressing the need to review and re-examine the functioning of the CBSE affiliated schools here, Okendra phoned CBSE chairman Vineet Joshi and asked to re-conduct the Physics paper examination.
http://www.hindustantimes.com/

### Due to General Elections CBSE Date sheet for 2014 Exams revised

In view of the schedule published by the Election Commission of India for the General Elections, 2014 the examinations of the Board in the following subjects for the Senior School Certificate (Class XII) Examination, 2014 have been postponed and will be now held on the revised dates indicated against the subject:
Dates in respect of other subjects will remain the same as notified earlier. All the stakeholders are requested to kindly make note of the revised schedule accordingly.

## Thursday, March 6, 2014

### CBSE class 12 students can get a copy of their evaluated answer sheets

"This is a welcome initiative of the CBSE board
Now, one of the most radical exam reforms, the Central Board of Secondary Education will allow Class XII students currently appearing for the board exams to not only get a copy of their evaluated answer sheets, but also seek re-evaluation instead of just a recount of the marks, sources told TOI.

Students can also specify which questions they want to be re-evaluated on. The facility will be open to those who apply for it and will be completely online — from availing a copy of the answersheet to requesting for re-evaluation.

According to CBSE sources, the exam committee has approved the move. However, as of now, it will be available only for English, Hindi, physics, chemistry, mathematics, political science and economics. There will also be a cap on the number of questions sought to be re-evaluated.

After a Supreme Court ruling, CBSE had, last year, provided photocopies of answersheets to candidates who had requested for it.

However, dissatisfied students had to be content with 'verification' of marks, which meant retotalling of marks given for each answer.

The provision of verification of marks/grades and obtaining photocopy of the evaluated answersheets will also continue. But in place of photocopies, candidates who apply will get a digitized version of the answer sheets.

"In the first year we are starting with seven major subjects. The facility will be extended to other subjects from subsequent exams. The board is in the process of finalizing the mode of delivery of the digitized answersheets. In case relatively low numbers of students apply for the answersheets, these can be delivered via email. Otherwise they will be allowed for download from the board's website," said a senior official in exam committee.

"This is a welcome initiative of the board and I applaud such a change in the CBSE evaluation pattern as even a mark or two makes a difference in college admission. I think it's a step in the right direction," said Anuradha Joshi, principal of Sardar Patel Vidyalaya.

CBSE sources said a student will be allowed to seek re-evaluation of only a specified number of answers. "A student is likely to have doubts in a certain number of answers and not on all answers evaluated. Therefore, we would be putting a limit on the number of questions for re-evaluation," the official said. The board will issue the detail modalities of the initiatives before the declaration of the results on the official website.
Courtesy: Times of India

## Wednesday, March 5, 2014

### Summative Assessment –II Solution of Mathematics class 10 CBSE Board 2014[Delhi] Set 1

Q1 The first three terms of an AP respectively are
3y – 1, 3y + 5 and 5y + 1. Then y equals:

(A) –3 (B) 4 (C) 5 (D) 2

Solution: (C) 5

Q2 In Fig. 1, QR is a common tangent to the given circles, touching externally at the point T. The tangent at T meets QR at P. If PT = 3.8 cm, then the length of QR (in cm) is :
(A) 3.8 (B) 7.6 (C) 5.7 (D) 1.9

Solution: (B) 7.6

Q3 In Fig. 2, PQ and PR are two tangents to a circle with centre O. If ∠QPR = 46°, then ∠QOR equals:
(A) 67° (B) 134° (C) 44° (D) 46°

Solution: (B) 134°

Q4. A ladder makes an angle of 60° with the ground when placed against a wall. If the foot of the ladder is 2 m away from the wall, then the length of the ladder (in metres) is:
(A) 43 (B) 43 (C) 22 (D) 4

Solution: (D) 4

Q5 If two different dice are rolled together, the probability of getting an even number on both dice, is:
(A) 136 (B) 12 (C) 16 (D) 14

Solution: (D) 14

Q6 A number is selected at random from the numbers 1 to 30. The probability that it is a prime number is:
(A) 23 (B) 16 (C) 13 (D) 1130

Solution: (C) 13

Q7 If the points A(x, 2), B(−3, −4) and C(7, − 5) are collinear, then the value of x is:
(A) −63 (B) 63 (C) 60 (D) −60

Solution: (A) −63

Q8 The number of solid spheres, each of diameter 6 cm that can be made by melting a solid metal cylinder of height 45 cm and diameter 4 cm, is:
(A) 3 (B) 5 (C) 4 (D) 6

Solution: (B) 5

SECTION- B

Q9 Solve the quadratic equation 2x2 + ax − a2 = 0 for x.

Solution: Comparing the given equation with the standard quadratic equation (ax2 + bx + c = 0),

We get:
a = 2, b = a and c =-a2

= - b ± /2a,

we get: x = - a ± / 2×2 =- a± /4 = (-a ± 3a)/4⇒ x= (- a+3a)/4 Þ

Þ x = a/2 or x= - a -3a / 4 = - a
So, the solutions of the given quadratic equation are x=a/2 or x = -a.

Q10. The first and the last terms of an AP are 5 and 45 respectively. If the sum of all its terms is 400, find its common difference.

Let a be the first term and d be the common difference.
Given: a = 5 Tn = 45 Sn = 400
We know:
Tn = a + (n − 1)d ⇒ 45 = 5 + (n − 1)d ⇒ 40 = (n − 1)d ... (i)
and Sn = n/2[a + Tn]
⇒400=n/2[5+45]⇒n/2=400/50 ⇒ n = 16
On substituting n = 16 in (i), we get:
40 = (16 − 1)d ⇒ 40 = (15)d ⇒ d = 40/15=8/3 Thus, the common difference is 8/3.

Q11 Prove that the line segment joining the points of contact of two parallel tangents of a circle, passes through its centre.

Solution:

Now, XB∥AO
⇒ ∠XBO + ∠AOB = 180° sum of adjacent interior angles is 180°)

Now, ∠XBO = 90° (A tangent to a circle is perpendicular to the radius through the point of contact)
⇒ 90° + ∠AOB = 180°
⇒ ∠AOB = 180° − 90° = 90°
Similarly, ∠AOC = 90°
∴ ∠AOB + ∠AOC = 90° + 90° = 180°
Hence, BOC is a straight line passing through O.
Thus, the line segment joining the points of contact of two parallel tangents of a circle, passes through its centre.

Q12 If from an external point P of a circle with centre O, two tangents PQ and PR are drawn such that ∠QPR = 120°, prove that 2PQ = PO.

Solution: We know that the radius is perpendicular to the tangent at the point of contact.
∴∠OQP=90∘
We also know that the tangents drawn to a circle from an external point are equally inclined to the segment, joining the centre to that point.

∴∠QPO=60∘
Now, in ∆QPO:
cos60∘ =PQ/ PO⇒1/2=PQ/PO⇒2PQ=PO

Q13 Rahim tosses two different coins simultaneously. Find the probability of getting at least one tail.
SA–II Subject Mathematics class 10 CBSE Board 2014[Delhi] All Sections

## Tuesday, March 4, 2014

### Code-30/3 Summative Assessment –II Solution Mathematics class 10 CBSE Board 2014

SECTION A

All questions are similar in 30/2 set

SECTION B

All questions are similar in 30/2 set except Q.No. 14

14. Find the value of p so that p x (x-3)+9 = 0 has equal roots.

SECTION C
All questions are similar in 30/2 set except Q. No. 20,22,23,24

20. Construct a triangle with side 5 cm, 5.5 cm and 6.5 cm . Now construct another triangle, whose sides are 3/5 times the corresponding sides of given triangle.

22. The sum of first seven term of AP is 182. If 4th and 17th term are in ratio 1: 5 . Find AP

23.From the top of 60m high building , the angle of depression of the top and bottom of a tower are 45 deg. and 60 deg. respectively. Find the height of tower.

24.Find a point p on y axis which is equidistant from points A(4,8)and B(-6,6)

SECTION D

All questions are similar in 30/2 set except Q.No.31, 32 and 34

31. (x – 4) / (x – 5 )/ (x – 6) / (x – 7 ) = 10/3

32. Five cards – the ten, jack ,queen king and ace of diamonds are are well suffled with their faces downward . one card are drawn randomly

(a)what is the probability that the drawn card is the queen

(b)If the queen is drawn and put aside , and a second card id drawn . find the probability that the second card is (i) an ace (ii) a queen

34. In fig. , A triangle ABC is drawn to circumscribe a circle of radius 4 cm , such that the segment BD and DC are of length 8 cm and 6 cm respectively. Find the side AB and AC

Maths class 10 CBSE Board Paper 2014 solution set-30/3 Solution.

Maths class 10 CBSE Board Paper 2014 solution Section A and B (code 30/2)

Maths class 10 CBSE Board Paper 2014 solution Section C and D (code 30/2)

Exams of 12th and 10th class students are always Crucial for students itself and also for there Families. So, here...

SA–II Subject Mathematics class 10 CBSE Board 2014[Delhi] Section A and B    Download File

## Monday, March 3, 2014

### Mathematics class 10 CBSE Board Paper 2014 solution Section A and B (code 30_2)

Series HRS Code-30/2 Summative Assessment –II Subject Mathematics class 10 CBSE Board 2014

SECTION-A

1. The probability that a number selected at random from the number 1,2,3,…..15. is a multiple of 4 is

(A)4/15 (B) 2/15 (C)1/5 (D)1/3
Ans: 1/5

2. The angle of depression of car parked on the road from the top of a 150m high tower is 300 . The distance of the car from the tower in m meter is

(A)50Ö3 (B)150Ö3 (C) 50Ö2 (D)75

Ans: (B)150Ö3

3. Two circle touches externally at P . AB is common tangent to the circle touching them at A and B . The value of <APB is

(A)300 (B)450 (C)600 (D) 900

Ans: (B)450

4. If k,2k -1 and 2k + 1 are three consecutive term of AP then value of k is

(A)2 (B)3 (C)-3 (D)5

Ans: (B)3

5. A chord of a circle of radius 10 cm subtends a right angle at its centre. The length of chord is

(A) 5Ö2 (B)10Ö2 (C)5/Ö2 (D)10Ö3

Ans: (B)10Ö2

6. ABCD is a rectangle whose three vertices are B(4,0), C(4,3) and D(0,3) . The length of one of its diagonal is

(A) 5 (B)4 (C)3 (D)25

Ans: (D)25

7. In a right triangle ABC , right angled at B ,BC = 12cm and AB = 5cm . The radius of circle inscribe in the triangle (in cm) is

(A) 4 (B)3 (C)2 (D) 1

Ans: (C)2

8. In a family of 3 children, the probability of having at least one boy is

(A) 7/8 (B)1/8 (C) 5/8 (D) ¾

Ans: (A) 7/8

SECTION-B

9.In fig-01,common tangent AB and CD to the circles with centers O1 and O2 intersect at E. Prove that AB=CD

Solution:

AE= CE [tangent from E] and CE = ED [tangent from E]

Adding them we get AE+ CE = CE + ED

AB = CD

10. The incircle of an isosceles triangle ABC , in which AB=AC, touches side BC , CA and AB at D,E and F respectively. Prove that BD = CD

Solution:

AB = AC

BF + AF = AE + CE --------(i)

BF = BD and CE = CD [tangent from B and C] -----------------(ii)

using (i)and (ii)

BD + AE = AE + CD

BD = CD

11. Two different dice are tossed together. Find the probability

(i) that the number on each side is even

(ii)The sum of the number appear on two dice is 5

Solution:

(i) Total favorable outcomes are 22,42,62,24,44,64,26,46,66 = 9

Number of all possible outcomes = 36

P[E] = 9/36= ¼

(ii) Total favorable outcomes are 41,32,23,14 = 4

Number of all possible outcomes = 36

P[E] = 4/36= 1/9

12. The total surface area of a solid hemisphere is 462cm2 , find the volume?

Ans: Total surface area of solid hemisphere= 3pr2

462 = 3 x 22/7 x r2

r = 7cm

Volume of solid hemisphere = 2/3 x pr3 = 2/3 x ( 22/7) x 7 x 7 x 7 = 2156/3 = 718.66cm3

13. Find the number of natural number between 101 and 199 which are by both 2 and 5.

Solution:

a1 = 110 and d = 10 an = 190

an = a + (n-1)d

190 = 110 + (n-1)10

(190 -110 )/10 = n-1

8+1= n

n = 9

Hence, there are 9 natural number between 101 and 199 which are by both 2 and 5.

14. Find the value of k for which the quadratic equation 9x2 – 3kx + k hs equal root.

Solution:

For equal root: D = 0

b2 – 4ac = 0

(- 3k)2 – 4 x 9 x k = 0

9k2 = 36k

k = 4 Hence, Value of k for which the quadratic equation 9x2 – 3kx + k ha equal root = 4

Maths class 10 CBSE Board Paper 2014 solution Section A and B (SET code 30/2) Download File

## Saturday, March 1, 2014

### Class IX Science Model Test Paper (Solved) For S.A. II 2014-2015-2016 onward

1 marks
1. Write the symbols of the following elements. (a) Iron (b) Silver

2. State the phylum to which antedon (feather star) and asterias (Starfish) belong.

3. Mention two factors that influence the pattern of winds.

2 marks

4. Distinguish between Bryophyta and Thallophyta stating two examples of each.

5. List the causative organisms for the following diseases.

(i) Kala-azar (ii) Sleeping sickness (iii) Acne (iv) AIDS

6. The volume of 50g of a substance is 20cm3. If the density of water is 1 g/cm3, will the substance float or sink in water ? Justify your answer.

7. What is the work done by the force of gravity in the following cases ?

(a) Satellite moving around the earth in a circular orbit of radius 35000 km.

(b) A stone of mass 250 g is thrown up through a height of 2.5 m.

3 marks

8. Define formula unit mass ? How is it calculated. ? Write the formula unit mass of (NH4)2 SO4 . (Given atomic mass : N = 14 u, H= 1 u, S = 32 u, O= 16 u).

9. (a) If an atom contains one electron and one proton Will it carry any charge or not ?

(b) On the basis of Thomson’s model of an atom explain how the atom is electrically neutral.

10. (a) If the K and L shells of an atom are full then what would be the number of electrons in the atom ?

(b) Helium atom has atomic mass of 4u and has 2 protons in its nucleus. How many neutrons does it have ?

(c) Why are isotopes of an element chemically similar ?

11. Draw diagram of hydra and label the following parts : Tentacles, Stinging cells, Gastrovascular Cavity, Epidermis

12. State appropriate terms for the following :

(i) Animals that are able to maintain a certain body temperature over a wide range of temperature in the environment

(ii) Plants which bear naked seeds (iii) Animals which have pseudocoelom.

13. (a) If penicillin is given to a patient suffering from Jaundice, it doesn’t have any effect on the infection. Why

(b) Name a disease which has been eradicated from the world.

(c) State the principle behind its eradication

14. What is meant by buoyancy ? Why does an object float or sink when placed on the surface of a liquid ?

15. (a) An arrow moves forward when released from a stretched bow. Explain the transformation of energy in the process.

(b) A boy of mass 50 kg climbs up a vertical height of 100 m. Calculate the amount of potential energy he gains.

16. (a) What is the commercial unit of energy ? Give its relationship with S.I. unit of energy. (b) An electric bulb of 60 W is lighted for 10 hrs. every day. How many units of electrical energy is consumed by this bulb in one day.

17. (a) Draw the sound waves for a low pitched and the high pitched sound. (b) Write one use of ultrasonography. (c) Which wave property determines pitch ?

18. (a) Name the process by which carbon is incorporated into life forms ? Also name a process by which carbon is recycled back into the atmosphere. (b) What would happen if the percentage of carbon dioxide increases in the atmosphere ?

19. (i) What is the main function of ozone layer that is present in the atmosphere ? (ii) How are CFC’s harmful to us ? (iii) What is smog ?

5 Marks

20. An element 147 A exists as diatomic gas in nature which is relatively inert and forms 78% of earth’s atmosphere.

(a) Identify the gas and write its molecular formula. Write the formulae of its nitrite and nitrate ions.

(b) How many moles of this gas would contain 12.0441023 atoms of this element. (Aragadros No= 6.22x1023)

(c) Calculate the molecular mass of : (i) NH4NO3 and(ii) HNO3 (Given atomic mass N=14 u, O=16 u H = 1 u)

OR

(a) A sample of vitamin C is known to contain 2.58 = 1024 oxygen atoms 168O How many moles of oxygen atoms are present in the sample. (Aragadros No= 6.22x1023)

(b) Write another elemental form of this element (oxygen). (c) Find the valency of oxygen in CO2 and MgO.

21. (a) State two characteristic features of vertebrates

(b) State reasons for each of the following statements

(i) Echidna and platypus lay eggs but considered as mammals. (ii) Forelimbs of birds are modified.

(iii) Crocodiles have four chambered heart but are still reptiles.

OR

(a) State two characteristic features of amphibians.

(b) Identify the following organisms.

i) Cold blooded animals that lay eggs in water and have three chambered heart

(ii) Spiny skinned organisms which have a peculiar water-drivern tube system that they use for moving around. (iii) Organisms which have an open circulatory system having blood filled coelomic cavity.

22. (a) Derive an expression for Kinetic energy of a body having mass ‘m’ and moving with a velocity v. (b) When velocity of a body is increased 5 times, what is the change in its kinetic energy ? (c) Two masses m and 2m are dropped from heights h and 2 h. On reaching ground, which will have a greater Kinetic Energy and why ?

OR,

(a) State the law of conservation of energy. (b) What is the work done to increase the velocity of a car from 36 km/hr to 72 km/hr if the mass of the car is 1500 kg. Does the work done by the force have a + ve or a - ve magnitude ? (c) Where does an oscillating pendulum has maximum PE and KE ?

23. (a) What is reverberation ? Write two ways of reducing reverberation. (b) Distinguish between tone and note.

(c) With the help of a simple diagram, explain how defects in a metal block can be detected using ultrasound.

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