## Wednesday, 12 November 2014

### Chapter 10. Mensuration CBSE Class VI (6th) Mathematics | Exercise 10.3 - Solutions

Things to remember...
• Area of a rectangle = length × breadth
• Area of the square = side × side
Question 1. Find the areas of the rectangles whose sides are :
(a) 3 cm and 4 cm
(b) 12 m and 21 m
(c) 2 km and 3 km
(d) 2 m and 70 cm

## Tuesday, 11 November 2014

### Chapter 10. Mensuration | CBSE Class 6th (VI) Mathematics | Exercise 10.2 - Solutions

Things to remember...
• The amount of surface enclosed by a closed figure is called its area.
• Surface Area of a figure  can be broken into exact numbers or approximate numbers of square units
• Depending upon the figure, some of square units may be completely covered, or partially covered.
• While using a squared paper, to calculate the area of a figure , we may use the  conventions :

## Monday, 10 November 2014

### Chapter 10. Mensuration | CBSE Class 6th (VI) Mathematics | Exercise 10.1 - Solutions

Things to remember...
• Perimeter is the distance covered once along the boundary of a closed figure .
• Perimeter of a rectangle = 2 × (length + breadth)
• Perimeter of a square = 4 × length of a side
• Perimeter of an equilateral triangle = 3 × length of a side
Question 1. Find the perimeter of each of the following figures :

## Sunday, 9 November 2014

### Chapter 11. Work and Energy - Science | MCQ - Multiple Choice Questions | CBSE Class 9th

Question 1. A dog weighing 25 kg, while chasing a cat, jumps over a fence of height 1.6 m. What is the potential energy of dog at the top of fence ?
(Take gravity due to earth 'g'=10 m s-2 )

(a) 160 Joules
(b) 320 Joules
(c) 380 Joules
(d) 480 Joules

## Sunday, 26 October 2014

### Chapter 10. Gravitation | Physics | MCQ - Multiple Choice Questions | CBSE Class 9th

Question 1. The value of acceleration due to gravity on the surface of the earth at sea level is

(a) 4.9 m/s2
(b) 6 m/s2
(c) 8 m/s2
(d) 9.8 m/s2

## Saturday, 25 October 2014

### Chapter 9 Force And Laws Of Motion | Physics | MCQs | Class 9th | - Multiple Choice Questions

Question 1. An object of mass 6 kg is sliding on  horizontal surface, with a uniform velocity of 8 m/ s . Assuming force of friction offered by the surface to be zero,  The force required to maintain the motion of object  with the same uniform velocity is

(a) 0 Newton
(b) 2 Newtons
(c) 8 Newtons
(d) 32 Newtons

### Chapter 8 Motion | Physics | MCQs | Class 9th | - Multiple Choice Questions

Question 1. A worker covers a distance of 40 km from his house to his place of work, and 10 km towards his house back. Then the displacement covered by the worker in the whole trip is

(a) zero km
(b) 10 km
(c) 30 km
(d) 50 km

## Wednesday, 13 August 2014

### Multiple Choice Questions - MCQs : Chapter 12. Electricity | CBSE Class 10th Science

Question 1. What happens to the resistance of circuit if current through it is doubled ?
(a) Resistance is doubled
(b) Resistance becomes half
(c) Resistance remains same
(d) None

Question 2. The work done in moving a unit positive charge, across two points in an electric circuit is measure of _____ ?
(a) Current
(b) Potential Difference
(c) Resistance
(d) Power

### Chapter 3 Drainage | Geography | CBSE Class 9th | Solved Exercises

Question 1. Choose the right answer from the four alternatives given below:

(i) Which one of the following describes the drainage patterns resembling the branches of a tree?

(b) Dendritic
(c) Centrifugal
(d) Trellis

### Chapter 13. WHY DO WE FALL ILL | CBSE Class 9th Science | Solved Exercises

Intext Questions | Page 178

Question 1. State any two conditions essential for good health.

Answer : A good health is ideally a state of well-being physically, mentally and socially . The two conditions essential for good health are:
1. All community members must have access to basic and better health care facilities supported by the qualified medical professionals.
2. There should be good economic opportunities for all. Community members should be socially well connected for any support or sharing of resources and should have high level of cleanliness and hygiene at personal or community level

## Saturday, 5 July 2014

### Exercise 1.3 Real Numbers | CBSE Class 10th Mathematics | Solutions

Question 1. Prove that √5 is irrational.

Solution : Let us assume, to the contrary, that √5 is rational.
That is, we can find integers a and b (≠ 0) such that :
 a √5 = b
Suppose a and b have a common factor other than 1, then we can divide by the common factor, and assume that a and b are coprime.
So, b √5 = a⋅

## Friday, 4 July 2014

### Real Numbers - Exercise 1.2 | CBSE Class 10th Mathematics | Solutions

Question 1. Express each number as a product of its prime factors:
(i) 140   (ii) 156    (iii) 3825   (iv) 5005    (v) 7429

Solution (i) To express the given number 140 as product of its prime factors, we employ the division method as shown below :

 2 | 140 2 | 70 5 | 35 7 | 7 | 1

∴ 140 = 2×2×5×7
= 22×5×7

## Points to remember

• An algorithm is a series of well defined steps which gives a procedure for solving a type of problem. The word algorithm comes from the name of the 9th century Persian mathematician al-Khwarizmi.
• A lemma is a proven statement used for proving another statement.
• Euclid’s Division Lemma : Given positive integers a and b, there exist unique integers q and r satisfying a = bq + r, 0 ≤ r < b.
• Euclid’s division algorithm : Euclid’s division algorithm is a technique to compute the Highest Common Factor (HCF) of two given positive integers. This is based on Euclid’s division lemma. According to this, the HCF of any two positive integers c and d, with c > d, is obtained as follows:

## Friday, 4 April 2014

### CBSE Class X (10th) Science | All Chapters Solved Exercises

This post contains chapter wise links to solutions of exercises   from  NCERT textbook of Science for Class 10th under CBSE. Each link for the chapter provides solutions to questions given in its main exercises including multiple choice questions, numericals, activities and in-text questions given after a main section to check the under standing of  the topic by students .

## Monday, 31 March 2014

### CBSE Class 10th Science | Chapter 16. Management of Natural Resources | Solved Exercises

In Text Questions | Page 269 |Chapter 16. Management of Natural Resources | CBSE Class 10th Science |

Question 1. What changes can you make in your habits to become more environment-friendly?

Answer. We can make certain positive changes in our habits to become more environment-friendly. We can follow the simple policy of the three R's i.e., Reduce, Reuse and Recycle
Which simply means that for our living,

## Saturday, 29 March 2014

### CBSE Class 10th Science | Chapter 15. Our Environment | Solved Exercises

In Text Questions | Page 257 |Chapter 15. Our Environment | CBSE Class 10th Science

Answer. Some substances can be acted upon by the micro organisms and broken down into simple substances. Such substances are called biodegradable.
Some substances are inert and cannot be acted upon by the microorganisms and do not breakdown into simple substances. Such substances are called non- biodegradable.

### CBSE Class 10th Science | Chapter 14. Sources of Energy | Solved Exercises

Question 1. A solar water heater cannot be used to get hot water on
(a) a sunny day.
(b) a cloudy day.
(c) a hot day.
(d) a windy day.

## Monday, 24 March 2014

### CBSE Class 10th Science | Chapter 13. Magnetic Effects of Electric Current | Solved Exercises

Question 1. Which of the following correctly describes the magnetic field near a long straight wire?
(a) The field consists of straight lines perpendicular to the wire.
(b) The field consists of straight lines parallel to the wire.
(c) The field consists of radial lines originating from the wire.
(d) The field consists of concentric circles centred on the wire.

Answer. (d) The field consists of concentric circles centred on the wire.

## Friday, 21 February 2014

### CBSE Class IX (9th) Science | All Chapters Solved Exercises

This post contains chapter wise links to solutions of exercises   from  NCERT textbook of Science for Class IX (9th) under CBSE. Each link, provides solutions to questions given in the  main exercises of the chapters,  including multiple choice questions, numericals and In Text questions given after a main section to check the under standing of  the topic by students .