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Doubtbox is the latest innovative product from the founders of eTutor, which is used by half a million students across the globe. This Interactive Digital Content Repository has 8000 animated topics and one lakh questions with answers for Classes 1-12 .

Doubtbox pen drive, an excellent tuition master at home, facilitating self learning by students, available for   Classes 1-12, based on CBSE syllabus, with effective blending of ICSE and State Boards syllabus. Once they are set up in the home computer/lap top, students can study any lesson according to their convenience and do home work easily, watching the lessons enriched with multimedia. All the topics are explained with quality animations, graphics, pictures and diagrams along with audio explanations. Students will enjoy lessons as if seeing an animated, topic-based film.

System Requirements:

  • Processor – Minimum:1 GHZ, RAM – Minimum:2 GB
  • Disk Space – Minimum 10 GB Free space
  • Screen resolution – 1280 x 720 or above
  • Operating System – Windows 7 or above

Doubtbox Features:

  • Latest syllabus
  • Animated video lessons
  • Exciting visuals
  • Audio explanations
  • Multiple choice questions
  • Assessments
  • Time bound test
  • Model test papers
  • Previous years question papers
  • NCERT solutions


Topics Covered in Doubtbox Educational Pen Drive

Chapter  1. Nutrition in Plants

Mode of nutrition in Plants, Photosynthesis-food making process  in plants, Other modes of nutrition in Plants,  Saprotrophs,  How Nutrients are Replenished in the Soil

Chapter  2. Nutrition in Animals

Different ways of taking Food,  Digestion in Humans – The Mouth and Buccal Cavity, The foodpipe/oesophagus, The Stomach, The Small Intestine, Absorption in the Small Intestine, Large Intestine,  Digestion in Grass-eating Animals,  Feeding and Digestion in Amoeba

Chapter  3. Fibre to Fabric

Wool – Animals that yield Wool,  From Fibres to Wool,  Processing Fibres into wool,  Silk- Life history of Silk Moth,  From Cocoon to Silk

Chapter  4. Heat

Hot and Cold, Measuring Temperature – Reading a Thermometer, Reading a Thermometer, Transfer Of Heat

Chapter  5. Acids, Bases and Salts

Acids and Bases,  Natural Indicators Around Us,  Neutralization,  Neutralizations in Everyday Life

Chapter  6. Physical and Chemical Changes

Physical Changes, Chemical Changes, Rusting of Iron, Crystallisation

Chapter  7. Weather, Climate and Adaptations of Animals to Climate

Weather,  Climate,  Climate and Adaptation- The Tropical Rainforests

Chapter 8. Winds, Storms and Cyclones

Air Exerts Pressure,  High Speed Winds are Accompanied by Reduced Air Pressure, Air Expands on Heating,  Wind Currents are Generated due to Uneven Heating on the Earth, Thunderstorms and Cyclones

Chapter 9. Soil

Soil Teeming with life,  Soil Profile, Soil Types,  Properties of Soil,  Absorption of water by Soil, Soil and Crops

Chapter  10. Respiration in Organisms

Why do we Respire?, Breathing,  How do we Breathe?, What do we Breathe out?, Breathing in other Animals, Breathing under Water,  Do plants also respire?

Chapter 11. Transportation in Animals  and Plants

Circulatory system – Blood, Blood vessels, Heart, Heart beat, Excretion in Animals, Transport of Substances in Plants

Chapter 12. Reproduction in Plants

Modes of reproduction- Asexual Reproduction, Vegetative propagation, Budding, Spore formation,  Fragmentation,  Sexual Reproduction- Pollination, Fertilization, Fruits and Seed formation,  Seed Dispersal

Chapter  13. Motion and Time

Slow or Fast,  Speed,  Measurement of Time,  Measuring Speed,  Distance-Time Graph

Chapter 14.  Electric Current and its Effects

Symbols of Electric Components,  Heating Effect of Electric Current,  Magnetic Effect of Electric Current, Electromagnet, Electric Bell

Chapter  15. Light

Light Travels Along a Straight Line, Reflection of Light,  Playing With Spherical Mirrors, Images formed by Lenses,  Sunlight – White or Coloured

Chapter 16.Water: A Precious Resource

How much Water is available, Forms of water, Groundwater as an important source of water, Depletion of Water Table, Distribution of Water, Water Management, What role you can play

Chapter 17.  Forests: Our Lifeline

Forest, Conservation of forest

Chapter 18. Waste Water Story

Water, our lifeline, What is Sewage? , Water freshens up – an  eventful journey,  Wastewater Treatment Plant (wwtp),  Better house keeping practices

Chapter 1. Integers

Introduction,  Properties of Addition and Subtraction of  Integers, Multiplication of Integers, Properties of Multiplication of Integers, Division of Integers, Properties of Division of Integers

Chapter 2. Fractions and Decimals

Introduction, How well have you learnt about Fractions?,  Multiplication of Fractions, Division of Fractions, How Well have you learnt about Decimal Numbers, Multiplication of Decimal Numbers,  Division of Decimal Numbers

Chapter 3. Data Handling

Introduction, Collecting Data,  Organisation of Data, Representative Values,  Arithmetic mean, Mode, Median, Use of Bar Graphs with a Different Purpose, Chance and Probability

Chapter 4. Simple Equations

A Mind-reading Game!, Setting up of an Equation, What Equation is?, More equations, Applications of Simple Equations to Practical Situations

Chapter 5. Lines and Angles

Introduction,  Related Angles,  Pairs of lines,  Checking for Parallel lines

Chapter 6. The Triangle and its properties

Introduction,  Medians of a Triangle,  Altitudes of a Triangle,  Exterior angle of a Triangle and its property,  Angle Sum Property of a Triangle,  Two Special Triangles : Equilateral and Isosceles, Sum of the Lengths of two Sides of a Triangle, Right-angled Triangles and  Pythagoras Property

Chapter 7. Congruence of Triangles

Introduction,  Congruence of Plane Figures,  Congruence of Triangles,  Criteria for Congruence of Triangles, Congruence among Right-angled Triangles

Chapter 8. Comparing Quantities

Introduction, Equivalent Ratios, Percentage – another way of Comparing Quantities, Use of Percentages , Prices related to an Item or Buying and Selling, Charge given on Borrowed Money or Simple Interest

Chapter 9. Rational Numbers

Introduction, What are Rational Numbers?, Positive and Negative Rational Numbers, Rational Numbers in Standard Form, Comparison of Rational Numbers, Rational Numbers between two Rational Numbers, Operations on Rational  Numbers

Chapter 10. Practical Geometry

Introduction, Construction of a line Parallel to a given line, through a point not on the line, Construction of Triangles, Constructing a Triangle when the Lengths of its Three Sides are known (SSS criterion),  Constructing a Triangle when the lengths of two sides and the measure of the angle between them are known (SAS criterion), Constructing a triangle when the measures of two of its angles and the length of the side included between them is given. (ASA criterion), Constructing a right-angled triangle when the length of one leg and its hypotenuse are given (RHS criterion)

Chapter 11. Perimeter and Area

Introduction, Squares and Rectangles, Area of a Parallelogram, Area of a Triangle, Circles, Conversion of Units, Applications

Chapter 12. Algebraic Expressions

Introduction, How are Expressions Formed? , Terms of an expression, Like and Unlike terms, Monomials, Binomials, Trinomials and Polynomials, Addition and Subtraction of Algebraic Expressions, Finding the Value of an expression, Using Algebraic Expressions – formulas and rules

Chapter 13. Exponents and Powers

Introduction, Exponents,  Laws of exponents, Miscellaneous Examples using the Laws of Exponents, Expressing Large Numbers in the Standard Form

Chapter 14. Symmetry

Introduction, Lines of symmetry for Regular Polygon, Rotational Symmetry, Line symmetry and Rotational symmetry

Chapter 15 . Visualising Solid Shapes

Introduction: Plane Figures and Solid Shapes, Faces, Edges and Vertices, Nets for building 3-D shapes, Viewing Different Sections of a Solid

Chapter 1. Present Tense

Introduction, Present tenses, Present tense aspects, Simple present tense, Present Continuous, Present perfect tense

Chapter 2. Past Tense

Past tense aspects, Past perfect, Simple past and present perfect tense

Chapter 3. Future Tense

Futurity in English, Future tense aspects, More on future tense, Using will and shall

Chapter 4. Adverbs

Introduction, Kinds of adverbs, Examples

Chapter 5. Adjectives

Definition, Types of Adjectives, As Attributive and Predicative, Degrees, Adjectives Table 1, Adjectives Table 2, Adjectives Table 3, Comparative form with To, Comparative into Positive, Superlative into Positive, Adjectives from Noun and verb, Conversation 1, Conversation 2, Special Adjectives, Examples

Chapter 6. Subject, Predicate and Object

Introduction, Subject, Predicate and Object, What is an object?, Examples of objects, Examples of predicates, Examples of subject

Chapter 7. Active voice and Passive Voice

Introduction, Active and Passive Voice, Example

Chapter 8. Question Tags

Introduction, Question Tags,  Seldom, Rarely etc

Chapter 9. Reported speech

Introduction,  Reporting Commands,  Reporting Questions, Reporting Statements

Chapter 10. Pronouns

Pronouns, More on Pronouns, Personal Pronouns, Demonstrative Pronouns, Possessive Pronouns, Reflexive Pronouns, Indefinite Pronouns

Chapter 11. Basic forms of ‘Be’

Basic forms of ‘Be’,  ‘Be’ used with Will, May, Can etc

Chapter 12.Positive, Negative and Question Modes

Positive, Negative and Question Modes

Chapter 13. Prepositions

Introduction, Objects of preposition 1, Objects of preposition 2, Prepositions with adjectives, Prepositions with forms of transport, Place and direction, Place and time, Examples

Chapter 14. Conjunctions

Conjunctions, Although, As, Because, Despite, In spite of, But, Neither nor, S0, Unless, While, Yet

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