trainee5's blog

Disclaimer: This website is NOT associated with CBSE, for official website of CBSE visit - www.cbse.gov.in

(Download) NCERT Exemplar Problems from Class 9 (Science)

CBSE TOPPER MODEL ANSWERS 2019 (CLASS-12) : English Core

model answer cbse Logo


CBSE TOPPER MODEL ANSWERS 2019 (CLASS-12)

English Core


  • Exam Name : CBSE Borad Exam Class - 12 Topper Model Answers 2019

  • Subject : En

CBSE Special TX: 
GENERAL: 
Subjects: 
Exam / Class: 

CBSE TOPPER MODEL ANSWERS 2019 (CLASS-12) : Business Studies

model answer cbse Logo


CBSE TOPPER MODEL ANSWERS 2019 (CLASS-12)

Business Studies


  • Exam Name : CBSE Borad Exam Class - 12 Topper Model Answers 2019

  • Subject

CBSE Special TX: 
GENERAL: 
Exam / Class: 

CBSE TOPPER MODEL ANSWERS 2019 (CLASS-12) : Economics

model answer cbse Logo


CBSE TOPPER MODEL ANSWERS 2019 (CLASS-12)

Economics


  • Exam Name : CBSE Borad Exam Class - 12 Topper Model Answers 2019

  • Subject : Econo

CBSE Special TX: 
GENERAL: 
Subjects: 
Exam / Class: 

CBSE TOPPER MODEL ANSWERS 2019 (CLASS-10) : Science

model answer cbse Logo


CBSE TOPPER MODEL ANSWERS 2019 (CLASS-10)

Science


  • Exam Name : CBSE Borad Exam Class - 10 Toppers Model Answers 2019

  • Subject : Scien

CBSE Special TX: 
GENERAL: 
Subjects: 
Exam / Class: 

CBSE TOPPER MODEL ANSWERS 2019 (CLASS-12) : Accountancy

model answer cbse Logo


CBSE TOPPER MODEL ANSWERS 2019 (CLASS-12)

Accountancy


  • Exam Name : CBSE Borad Exam Class - 12 Topper Model Answers 2019

  • Subject : Acc

CBSE Special TX: 
GENERAL: 
Exam / Class: 

NCERT Mathematics Question Paper (Class - 11)

NCERT Mathematics Question Paper (Class - 11)


(Mathematics) : Chapter 1 Sets


EXERCISE 1.1

Question 1. Which of the following are sets ? Justify your asnwer.

(i) The collection of all the months of a year beginning with the letter J.
(ii) The collection of ten most talented writers of India.
(iii) A team of eleven best-cricket batsmen of the world.
(iv) The collection of all boys in your class.
(v) The collection of all natural numbers less than 100.
(vi) A collection of novels written by the writer Munshi Prem Chand.
(vii) The collection of all even integers.
(viii) The collection of questions in this Chapter. (ix) A collection of most dangerous animals of the world.

Question 2. Let A = {1, 2, 3, 4, 5, 6}. Insert the appropriate symbol ∈ or in the blank spaces:

(i) 5. . .A
(ii) 8 . . . A
(iii) 0. . .A
(iv) 4. . . A
(v) 2. . .A
(vi) 10. . .A

Question 3. Write the following sets in roster form:

(i) A = {x : x is an integer and –3 < x < 7}
(ii) B = {x : x is a natural number less than 6}
(iii) C = {x : x is a two-digit natural number such that the sum of its digits is 8}
(iv) D = {x : x is a prime number which is divisor of 60}
( v) E = The set of all letters in the word
(vi) F = The set of all letters in the word

Question 4. Write the following sets in the set-builder form :

(i) (3, 6, 9, 12}
(ii) {2,4,8,16,32}
(iii) {5, 25, 125, 625}
(iv) {2, 4, 6, . . .} (v) {1,4,9, . . .,100}

Question 5. List all the elements of the following sets :

(i) A = {x : x is an odd natural number}
(ii) B = {x : x is an integer, 1 2 – < x 9 2 }
(iii) C = {x : x is an integer, x2 ≤ 4}
(iv) D = {x : x is a letter in the word “LOYAL”}
(v) E = {x : x is a month of a year not having 31 days}
(vi) F = {x : x is a consonant in the English alphabet which precedes k }.

Question 6. Match each of the set on the left in the roster form with the same set on the right described in set-builder form:

(i) {1, 2, 3, 6} (a) {x : x is a prime number and a divisor of 6}
(ii) {2, 3} (b) {x : x is an odd natural number less than 10}
(iii) {M,A,T,H,E,I,C,S} (c) {x : x is natural number and divisor of 6}
(iv) {1, 3, 5, 7, 9} (d) {x : x is a letter of the word MATHEMATICS}.

GENERAL: 
Subjects: 
Exam / Class: 
Tags: 

NCERT Physics Question Paper (Class - 11)

NCERT Physics Question Paper (Class - 11)


:: Chapter 1 Physical World ::


Question 1.1 Some of the most profound statements on the nature of science have come from Albert Einstein, one of the greatest scientists of all time. What do you think did Einstein mean when he said : “The most incomprehensible thing about the world is that it is comprehensible”?

Question 1.2 “Every great physical theory starts as a heresy and ends as a dogma”. Give some examples from the history of science of the validity of this incisive remark.

Question 1.3 “Politics is the art of the possible”. Similarly, “Science is the art of the soluble”. Explain this beautiful aphorism on the nature and practice of science.

Question 1.4 Though India now has a large base in science and technology, which is fast expanding, it is still a long way from realising its potential of becoming a world leader in science. Name some important factors, which in your view have hindered the advancement of science in India.

Question 1.5 No physicist has ever “seen” an electron. Yet, all physicists believe in the existence of electrons. An intelligent but superstitious man advances this analogy to argue that ‘ghosts’ exist even though no one has ‘seen’ one. How will you refute his argument ?

Question 1.6 The shells of crabs found around a particular coastal location in Japan seem mostly to resemble the legendary face of a Samurai. Given below are two explanations of this observed fact. Which of these strikes you as a scientific explanation ?

(a) A tragic sea accident several centuries ago drowned a young Samurai. As a tribute to his bravery, nature through its inscrutable ways immortalised his face by imprinting it on the crab shells in that area
(b) After the sea tragedy, fishermen in that area, in a gesture of honour to their dead hero, let free any crab shell caught by them which accidentally had a shape resembling the face of a Samurai. Consequently, the particular

shape of the crab shell survived longer and therefore in course of time the shape was genetically propagated. This is an example of evolution by artificial selection. [Note :This interesting illustration taken from Carl Sagan’s ‘The Cosmos’ highlights the fact that often strange and inexplicable facts which on the first sight appear ‘supernatural’ actually turn out to have simple scientific explanations. Try to think out other examples of this kind].

Question 1.7 The industrial revolution in England and Western Europe more than two centuries ago was triggered by some key scientific and technological advances. What were these advances ?

Question 1.8 It is often said that the world is witnessing now a second industrial revolution, which will transform the society as radically as did the first. List some key contemporary areas of science and technology, which are responsible for this revolution.

GENERAL: 
Subjects: 
Exam / Class: 

CBSE TOPPER MODEL ANSWERS 2019 (CLASS-12) : Biology

model answer cbse Logo


CBSE TOPPER MODEL ANSWERS 2019 (CLASS-12)

Biology


  • Exam Name : CBSE Borad Exam Class - 12 Topper Model Answers 2019

  • Subject : Biology

CBSE Special TX: 
GENERAL: 
Subjects: 
Exam / Class: 

CBSE TOPPER MODEL ANSWERS 2019 (CLASS-10) : Hindi Course A & B

model answer cbse Logo

CBSE TOPPER MODEL ANSWERS 2019 (CLASS-10)

Hindi Course A & B

Exam Name : CBSE Borad Exam Class - 10 Toppers Model Answers 2019

Subject : Hindi Course A & B (Model Answer)

Year : 2019

<

download

(E-Book) CBSE Board Class 10th Model Answers PDF : Hindi

Click Here to Download Hindi Course A​

CBSE Special TX: 
GENERAL: 
Subjects: 
Exam / Class: 

CBSE TOPPER MODEL ANSWERS 2019 (CLASS-10) : English Language & Literature

model answer cbse Logo


CBSE TOPPER MODEL ANSWERS 2019 (CLASS-10)

English Language & Literature


  • Exam Name : CBSE Borad Exam Class - 10 Toppers Model Answers 2019

  • <
CBSE Special TX: 
GENERAL: 
Subjects: 
Exam / Class: 

CBSE TOPPER MODEL ANSWERS 2019 (CLASS-12) : Chemistry

model answer cbse Logo


CBSE TOPPER MODEL ANSWERS 2019 (CLASS-12)

Chemistry


  • Exam Name : CBSE Borad Exam Class - 12 Topper Model Answers 2019

  • Subject : Chemi

CBSE Special TX: 
GENERAL: 
Subjects: 
Exam / Class: 

NCERT Biology Question Paper (Class - 11)

NCERT Biology Question Paper (Class - 11)


(Biology) Chapter 1 The Living World


Question 1: Why are living organisms classified?

Question 2: Why are the classification systems changing every now and then?

Question 3: What different criteria would you choose to classify people that you meet often?

Question 4: What do we learn from identification of individuals and populations?

Question 5: Given below is the scientific name of Mango. Identify the correctly written name. Mangifera Indica

Question 6: Define a taxon. Give some examples of taxa at different hierarchical levels.

Question 7: Can you identify the correct sequence of taxonomical categories?

(a) Species → Order → Phylum → Kingdom
(b) Genus → Species → Order → Kingdom
(c) Species → Genus → Order → Phylum

Question 8: Try to collect all the currently accepted meanings for the word ‘species’. Discuss with your teacher the meaning of species in case of higher plants and animals on one hand and bacteria on the other hand.

Question 9: Define and understand the following terms: (i) Phylum (ii) Class (iii) Family (iv) Order (v) Genus

Question 10: How is a key helpful in the identification and classification of an organism?

Question 11: Illustrate the taxonomical hierarchy with suitable examples of a plant and an animal.

GENERAL: 
Subjects: 
Exam / Class: 
Tags: 

NCERT Chemistry Question Paper (Class - 11)

NCERT Chemistry Question Paper (Class - 11)


(Chemistry) Chapter 1 Some Basic Concepts Of Chemistry


NCERT Exercises Questions

Question 1.1 Calculate the molecular mass of the following :
(i) H2O
(ii) CO2
(iii) CH4

Question 1.2 Calculate the mass per cent of different elements present in sodium sulphate (Na2SO4).

Question 1.3 Determine the empirical formula of an oxide of iron which has 69.9% iron and 30.1% dioxygen by mass.

Question 1.4 Calculate the amount of carbon dioxide that could be produced when
(i) 1 mole of carbon is burnt in air.
(ii) 1 mole of carbon is burnt in 16 g of dioxygen.
(iii) 2 moles of carbon are burnt in 16 g of dioxygen.

Question 1.5 Calculate the mass of sodium acetate (CH3COONa) required to make 500 mL of 0.375 molar aqueous solution. Molar mass of sodium acetate is 82.0245 g mol–1.

Question 1.6 Calculate the concentration of nitric acid in moles per litre in a sample which has a density, 1.41 g mL–1 and the mass per cent of nitric acid in it being 69%.

Question 1.7 How much copper can be obtained from 100 g of copper sulphate (CuSO4) ?

Question 1.8 Determine the molecular formula of an oxide of iron in which the mass per cent of iron and oxygen are 69.9 and 30.1 respectively.

Question 1.9 Calculate the atomic mass (average) of chlorine using the following data : % Natural Abundance Molar Mass 35Cl 75.77 34.9689 37Cl 24.23 36.9659

Question 1.10 In three moles of ethane (C2H6), calculate the following :
(i) Number of moles of carbon atoms.
(ii) Number of moles of hydrogen atoms.
(iii) Number of molecules of ethane.

Question 1.11 What is the concentration of sugar (C12H22O11) in mol L–1 if its 20 g are dissolved in enough water to make a final volume up to 2L?

Question 1.12 If the density of methanol is 0.793 kg L–1, what is its volume needed for making 2.5 L of its 0.25 M solution?

Question 1.13 Pressure is determined as force per unit area of the surface. The SI unit of pressure, pascal is as shown below : 1Pa = 1N m–2 If mass of air at sea level is 1034 g cm–2, calculate the pressure in pascal.

Question 1.14 What is the SI unit of mass? How is it defined?

Question 1.15 Match the following prefixes with their multiples: Prefixes Multiples
(i) micro 106
(ii) deca 109
(iii) mega 10–6
(iv) giga 10–15
(v) femto 10

Question 1.16 What do you mean by significant figures ?

Question 1.17 A sample of drinking water was found to be severely contaminated with chloroform, CHCl3, supposed to be carcinogenic in nature. The level of contamination was 15 ppm (by mass).
(i) Express this in percent by mass.
(ii) Determine the molality of chloroform in the water sample.

Question 1.18 Express the following in the scientific notation:
(i) 0.0048
(ii) 234,000
(iii) 8008
(iv) 500.0
(v) 6.0012

GENERAL: 
Subjects: 
Exam / Class: 
Tags: 

CBSE TOPPER MODEL ANSWERS 2019 (CLASS-12) : Physics

model answer cbse Logo


CBSE TOPPER MODEL ANSWERS 2019 (CLASS-12)

Physics


  • Exam Name : CBSE Borad Exam Class - 12 Topper Model Answers 2019

  • Subject : Physics

CBSE Special TX: 
GENERAL: 
Subjects: 
Exam / Class: 

CBSE TOPPER MODEL ANSWERS 2019 (CLASS-10) : English Communicative

model answer cbse Logo


CBSE TOPPER MODEL ANSWERS 2019 (CLASS-10)

English Communicative


  • Exam Name : CBSE Borad Exam Class - 10 Toppers Model Answers 2019

  • S

CBSE Special TX: 
GENERAL: 
Subjects: 
Exam / Class: 

Pages

Subscribe to RSS - trainee5's blog