Topics
Gravitation
- Gravitation
- Force
- Motion and Rest
- Uniform Circular Motion (UCM)
- Centripetal Acceleration and Centripetal Force
- Kepler’s Laws
- Newton’s Universal Law of Gravitation
- Earth’s gravitational force
- Acceleration Due to Gravity (Earth’s Gravitational Acceleration)
- Mass and Weight of an Object
- Free Fall
- Gravitational Potential Energy
Periodic Classification of Elements
- History of Periodic Table: Early Attempts at the Classification of Elements
- Dobereiner’s Triads
- Newland's Law of Octaves
- Mendeleev’s Periodic Table
- Merits and Demerits of Mendeleev’s Periodic Table
- Modern Periodic Law
- The Modern Periodic Table
- Types of Element on the Basis of Periodic Table
- Groups and Electronic Configuration
- Modern Periodic Table and Electronic Configuration of Elements
- Periodic Properties
- Periodic Properties: Valency
- Periodic Properties: Atomic Radius Or Atomic Size
- Periodic Properties: Metallic Character
- Periodic Properties: Non-metallic Character
- Study of Specific Groups in Periodic Table
- Group VIIA Or Group 17 (The Halogens)
Chemical Reactions and Equations
- Chemical Reaction
- Classification of Change: Chemical Changes
- Chemical Equation
- Balancing Chemical Equation
- Types of Chemical Change or Chemical Reaction
- Direct Combination (or Synthesis) Reaction
- Decomposition Reactions
- Single Displacement Reactions
- Double Displacement Reaction
- Energy Change in Chemical Reactions
- Rate of Chemical Reaction
- Factors Affecting the Rate of a Chemical Reaction
- Oxidation, Reduction and Redox Reactions
- Corrosion of Metals and Its Prevention
- Rancidity of Food and Its Prevention
Effects of Electric Current
- Electric Circuit
- Ohm's Law (V = IR)
- Joule’s Law of Heating
- Electrical Power
- Heating Effect of Electric Current
- Magnetic Effect of Electric Current
- Electric Fuse
- Rule to Find the Direction of Magnetic Field
- Magnetic Field Due to Current in a Loop (Or Circular Coil)
- Magnetic Field Due to a Current Carving Cylindrical Coil (or Solenoid)
- Force on a Current Carrying Conductor in a Magnetic Field
- Electric Motor
- Electromagnetic Induction
- Faraday's Laws of Electromagnetic Induction
- Galvanometer
- Types of current: Alternating Current (A.C.) and Direct Current (D.C.)
- Electric Generator
- Alternating Current (A.C.) Generator
- Direct Current Motor
Heat
Refraction of Light
Lenses
- Lens
- Spherical Lens
- Images Formed by Sperical Lenses
- Guideline for Image Formation Due to Refraction Through a Convex and Concave Lens
- Concave Lens
- Images Formed Due to Refraction Through a Concave Lens
- Convex Lens
- Images Formed Due to Refraction Through a Convex Lens
- Sign Convention for Spherical Lenses
- Lens Formula
- Magnification Due to Spherical Lenses
- Power of a Lens
- Combination of Lenses
- Human Eye: Structure of the Eye
- Working of the Human Eye
- Eye Defect and Its Correction: Myopia Or Near-sightedness
- Eye Defect and its correction: Hypermetropia or far-sightedness
- Eye Defect and Its Correction: Presbyopia
Metallurgy
- Types of Elements: Metals
- Physical Properties of Metals
- Chemical Properties of Metal
- Types of Elements: Non-metal
- Physical Properties of Non-metal
- Chemical Properties of Non-metal
- Reactivity Series of Metals
- Electrovalent (or Ionic) Bond
- Ionic Compounds and Electrical Conductivity
- Metallurgy
- Types of Separation or Concentration of an Ore
- Extraction of Metals
- Extraction of Aluminium
- Refining of Metals
- Corrosion of Metals and Its Prevention
Carbon Compounds
- Carbon: a Versatile Element
- Classification of Compounds of Carbon
- The Covalent Bond
- Types of Covalent Bond
- Formation of Covalent Bond
- Special Features of Carbon
- Hydrocarbons
- Chains, Branches and Rings of Carbon Compound
- Functional Groups in Carbon Compounds
- Homologous Series of Carbon Compound
- Nomenclature of Organic Compounds (IUPAC)
- IUPAC Nomenclature of Hydrocarbons
- IUPAC Nomenclature of other classes
- Chemical Properties of Carbon Compound
- Ethanol
- Ethanoic Acid
- Macro Molecules and Polymers
Space Missions
- Space Missions
- Satellites
- Types of Satellite
- Orbits of Artificial Satellites
- Launching of Satellite
- Space Missions Away from Earth
- India’s Space Programmes: Chandrayaan – 1
- India’s Space Programmes: Chandrayaan – 2
- India’s Space Programmes: Mangalyaan (Mars vehicle)
- India’s Space Programmes: Missions to Other Planets
- India and Space Technology
- Space Debris and Its Management
School of Elements
The Magic of Chemical Reactions
The Acid Base Chemistry
- Properties of Acids
- Strength of Acidic or Basic Solutions
- Strength of Acidic or Basic Solutions
- Acids, Bases and Their Reactivity
- Acid or a Base in a Water Solution
- Preparation and Uses of Baking Soda
- Preparation and Uses of Bleaching Powder
- Preparation and Uses of Washing Soda
- Preparation and Uses of Plaster of Paris
- Chemicals from Common Salt - Soap as a Salt
The Electric Spark
All about Electromagnetism
- Magnetic Force
- The Bar Magnet
- Rule to Find the Direction of Magnetic Field
- Magnetic Field Due to Current in a Loop (Or Circular Coil)
- Magnetic Field Due to a Current Carving Cylindrical Coil (or Solenoid)
- Force on a Current Carrying Conductor in a Magnetic Field
- Electric Motor
- Electromagnetic Induction
- Alternating Current (A.C.) Generator
- Direct Current Motor
- Household Electrical Circuits
Wonders of Light 1
- Spherical Mirrors
- Concave Mirror
- Concave Mirror
- Sign Convention for Reflection by Spherical Mirrors
- Linear Magnification (M) Due to Spherical Mirrors
- Images Formed by Sperical Lenses
- Convex Lens
- Convex Lens
- Sign Convention for Spherical Lenses
- Magnification Due to Spherical Lenses
- Power of a Lens
- Human Eye: Structure of the Eye
- Eye Defect and Its Correction: Myopia Or Near-sightedness
- Spherical Mirrors
Wonders of Light 2
Striving for better Environment 1
- Pollution and Its Types
- Air Pollution and Its Causes
- Air Pollution and Its Causes
- Effects of Air Pollution
- Water Pollution and Its Causes
- Water Pollution and Its Causes
- Effects of Water Pollution
- Soil Pollution
- Effects of Soil Pollution
- Noise Pollution
- Radioactive Pollution and Effects
- Abatement of Pollution
- Sustainable Use of Resources
- Motion of objects under the influence of gravitational force of the earth
- Escape velocity
Notes
MOTION OF OBJECTS UNDER THE INFLUENCE OF GRAVITATIONAL FORCE OF THE EARTH:
As g is constant near the earth, all the equations for the uniformly accelerated motion of objects become valid with acceleration a replaced by g. The equations are:
v = u + at
s = ut + 1/2at2
v2 = u2 + 2as
where u and v are the initial and final velocities and s is the distance covered in time, t. In applying these equations, we will take acceleration, a to be positive when it is in the direction of the velocity, that is, in the direction of motion. The acceleration, a will be taken as negative when it opposes the motion.
Notes
Free Fall:
Whenever objects fall towards the earth under this force alone, we say that the objects are in free fall. Is there any Whenever objects fall towards the earth under this force alone, we say that the objects are in free fall. Is there any But due to the earth’s attraction, there will be a change in the magnitude of the velocity. Any change in velocity involves acceleration. Whenever an object falls towards the earth, an acceleration is involved. This acceleration is due to the earth’s gravitational force. Therefore, this acceleration is called the acceleration due to the gravitational force of the earth (or acceleration due to gravity). It is denoted by g. The unit of g is the same as that of acceleration, that is, ms–2.
As
F = ma (`because`a = g) ...(1)
F = mg ...(2)
and `"F" = "G"("Mm")/"d"^2` (`therefore` Universal law of gravitation) ...(3)
From (ii) and (iii)
`therefore` `"mg" = "G"("Mm")/"d"^2`
`therefore` `"g" = "GM"/"d"^2`
M = Mass of the earth.
d = Distance between the object and the earth.
G = Gravitational constant
If the object is placed on the earth then d = R (radius of the earth)
`therefore` `"g" = "GM"/"R"^2`
Earth is not a sphere it is flattened at poles.
Hence Rp - Radius at pole and Re - Radius at equator Re > Rp
`"g" ∝ 1/"R"`
`therefore` The value of 'g' is more at poles = (9.9 m/s2) and less at the equator = (9.8 m/s2)