CBSE Class 9 - CH 4.2 Linear equations in two variables (NCERT Ex 4.2)

Linear Equations in Two Variables

Exercise 4.2

Q1: Which one of the following options is true, and why?

     y = 3x + 5 has

(i) a unique solution, (ii) only two solutions, (iii) infinitely many solutions
Answer:

y = 3x + 5 is a linear equation in two variables and it has infinite possible solutions. As for every value of
x, there will be a value of y satisfying the above equation and vice-versa.

Hence, the correct answer is (iii).


Q2: Write four solutions for each of the following equations:

(i) 2x + y = 7 (ii) ∏x + y = 9 (iii) x = 4y

CBSE Class 9 - Geography - Physical Features of India (Short Questions and Answers)

Physical Features of India

Q & A

Physiographic divisions

Q1: Discuss the geological structure of India.

Answer: Geological structure of India:

1. India is part of ancient continent called Gondwanaland which is divided into many plates. One such Indo-Australian plate moved towards the north and collided with Euro-asian plate and thus resulted in rising to the present day Himalayas. 
2. To the south of Himalayas a basin was formed. It was filled with alluvium brought by the rivers and thus forming North Indian plains.
3. During Himalayas formation, two major events affected the plateau. An extensive volcanic eruption took place in the north-west part of the plateau.
4. The western part subsided and the Indian Ocean advanced and occupied the depression. It led to the rise to the Bay of Bengal and the Arabian sea.

Q2: Describe the physiographic divisions or physical features of India.

Answer: Physiographic division of India is:

1. The Himalayan Mountains: Geologically young and fold mountains stretch over the northern borders of India. These are the one of the most rugged mountain barriers of the world.
2. The Northern Plain: It is about 2400km long and 240-320km wide. Formed by interplay of three major river systems - the Indus, the Ganga and the Brahamputra. It is rich in fertile alluvial soil.
3. The Peninsular Plateau: The tableland composed of old crystalline igenous and metamorphic rocks. It is abundant with shallow valleys and rounded hills.
4. The Indian Desert: It lies towards the western margins of the Aravalli Hills and has arid climate with low vegetation cover.
5. The Coastal Plains: These plains are stretched along the eastern and the western edges of the peninsular plateau.
6. The Islands: Two island groups - The Lakshadweep Islands and the Andaman and Nicobar Islands.

Q3: Write three important features of Aravalli Hills.

CBSE Class 9 - Science - CH1 Matter In Our Surroundings (Question Bank)

Matter In Our Surroundings

Questions asked in CBSE Examination

Very Short Answer Type (1 Mark)

Q1: Expand CNG and LPG.

Q2: Which will have more impact on kinetic energy; doubling mass or doubling velocity?

Q3: Arrange the following substances in increasing order of force of attraction between the particles.

       (i) milk (ii) salt (iii) oxygen

Q4: Why is sponge a solid though compressible?

Q5: Write one important characteristic of matter.

Q6: Why does a desert cooler cool better in a hot dry day?

Q7: Convert:

(a) 25°C into kelvin scale

(b) 500 K into celsius scale

Q8: Why does the smell of hot sizzling food reach you several metres away but to get the smell

from cold food you have to go close?

Q9: What is the term used for change of solid state to liquid state? 

Q10: Name the temperature at which solid and liquid states of matter can coexist.

Q11: Define evaporation.

CBSE Class 9 : Maths - CH 4.1 - Linear equations in two variables (NCERT Ex 4.1)

Linear Equations In Two Variables

Q1: The cost of a notebook is twice the cost of a pen. Write a linear equation in two variables to represent this statement.

(Take the cost of a notebook to be Rs x and that of a pen to be Rs y.)

Answer:

Let the cost of a notebook and a pen be x and y respectively.

Cost of notebook = 2 ☓ Cost of pen

x = 2y

x − 2y = 0

Q2: Express the following linear equations in the form ax + by + c = 0 and indicate the values of a, b, c in each case:

(i) 2x + 3y = 9.35  

(ii) x - y/5 - 10 = 0
(iii) − 2x + 3 y = 6

(iv) x = 3y
(v) 2x = − 5y
(vi) 3x + 2 = 0

(vii) y − 2 = 0
(viii) 5 = 2x

Answer:

CBSE Class 10 - Science - Ch6 - Gist on Excretory System (Life Processes)

Gist on Excretory System

(Short Q & A)

A Pair Of Kidneys
(image credits: openclipart)

Q1: Define Excretion.

Answer: Excretion is a biological process by which an organism gets rid of metabolic toxic wastes from its body.

Q2: List the toxic wastes of metabolism.

Answer: These wastes are nitrogenous materials i.e. ammonia, urea and uric acid, carbon dioxide, inorganic salts, excess of water.

Q3: What is Osmoregulation? 

Answer: It is a process that maintains the amount of water and ionic balance in the body.

Q4: Where Urea is formed in mammals?

Answer: Urea is made in the liver via the ornithine cycle by combining the ammonia
made by deamination with carbon dioxide made from respiration

Q5: What are the major excretory products of plants?

CBSE Class 11 - Computer Science - CH6 - Getting Started With C++ (Sumita Arora Textbook Solutions)

Getting Started With C++
(Sumita Arora) Textbook Solutions 7th Edn

credits:openclipart

SHORT ANSWER QUESTIONS

Q1: What are tokens in C++? How many types of tokens allowed in C++? Exemplify your answer.

Answer: A token is the smallest unit of a c++ program that can be processed by a c++ compiler. These are also called lexical units or lexical elements. C++ has the following tokens:

• Keywords: Reserved words which have special meaning or purpose. e.g. for, const, while, class, struct etc.
• Identifiers: These are the names given to variables, constants, arrays, functions, classes or objects of a c++ program. Identifiers are case sensitive in c++. e.g. valid identifiers are: student, Date123, file234 etc.
• Literals: Data Items that never change their value during program run. Also called constants. In C++ there are five types of literals i.e. bool literal, integer constants, character constants, floating constants and string literals. e.g. 1234, 'b', 3.14 etc.
• Punctuators: These are tokens which have syntactic and semantic meaning to the compiler. e.g. {}, =, ++, -, %, *= etc.
• Operators: These are the tokens that tell the c++ compiler to perform specific mathematical or logical manipulations. C++ is full of operators. e.g. Arithmetic operators(+,-,*,/,%), Shift operators(<<. >>), Bitwise operators(&, ^, |), logical operators(&&, ||) etc.

CBSE Class 7 - Civics - CH2 - ROLE OF GOVERNMENT IN HEALTH

ROLE OF GOVERNMENT IN HEALTH

NCERT TEXTBOOK QUESTIONS WITH ANSWERS

Q1: In this chapter you have read that health is a wider concept than illness. Look at this quote from the Constitution and explain the terms ‘living standard’ and ‘public health’ in your own words.

 An important part of the Constitution says it is the “duty of the State to raise the level of nutrition and the standard of living and to improve public health.”

Answer: Living Standard: is the environment, the atmosphere built across the surroundings of people
living in different regions.In well constructed urban areas standard of living is far better in
comparison to underdeveloped rural areas.Clean, pollution free surroundings lead to good living standards.
Whereas living in regions of dirty, poor sanitation, dusty lands leads to poor living standards.

Public Health: It is the wellness of all people, whether rich or poor, educated or uneducated, man or woman etc. to remain  healthy and free of any disease. Right to life is everyone's right without any discrimination. That is why it is named as "public" health and every individual can have the facilities given by the government in this respect.


Q2: What are the different ways through which the government can take steps to provide healthcare for all?Discuss.