Study Material

    • World Energy Needs
      7th-class Science Chapter 28  
      Energy is an important ingredient in all phases of society. We live in a very interdependent world, and access to adequate and reliable energy resources is crucial for economic growth and for maint...
    • Heat Energy Transfers
      7th-class Science Chapter 27  
      Heat transfer is a discipline of thermal engineering that concerns the generation, use, conversion, and exchange of thermal energy (heat) between physical systems. Heat transfer is classified into ...
    • Energy Transfers
      7th-class Science Chapter 26  
      forms of energy: thermal (heat), light, electrical, sound, kinetic, chemical, nuclear and potential (elastic and gravitational) Conservation of energy : energy is never created or destroyed, it ...
    • Energy
      7th-class Science Chapter 25  
      Energy cannot be created or destroyed, only converted from one form to another. These conversions can be shown in Sankey diagrams. Efficiency is a measure of how much useful energy is converted...
    • Speed
      7th-class Science Chapter 24  
      In everyday use and in kinematics, the speed of an object is the magnitude of its velocity (the rate of change of its position); it is thus a scalar quantity.The average speed of an object in an in...
    • Turning of a Pivot
      7th-class Science Chapter 23  
      In physics, a moment is an expression involving the product of a distance and a physical quantity, and in this way it accounts for how the physical quantity is located or arranged. Moments are usua...
    • Forces and Motion
      7th-class Science Chapter 22  
      At terminal velocity the gravitational force down equals the air resistance force up. vehicle stopping distance depends on the speed squared. moment = force × perpendicular distance from pivot ...
    • Density
      7th-class Science Chapter 21  
      The density, or more precisely, the volumetric mass density, of a substance is its mass per unit volume. The symbol most often used for density is ρ (the lower case Greek letter rho), although ...
    • Measurements
      7th-class Science Chapter 20  
      Measurement is the assignment of a number to a characteristic of an object or event, which can be compared with other objects or events.The scope and application of measurement are dependent on the...
    • Periodic Table
      7th-class Science Chapter 19  
      The periodic table is a tabular arrangement of the chemical elements, ordered by their atomic number, electron configuration, and recurring chemical properties, whose structure shows periodic trend...
    • Metals & Non Metals
      7th-class Science Chapter 18  
      A metal is a material (an element, compound, or alloy) that is typically hard when in solid state, opaque, shiny, and has good electrical and thermal conductivity. Metals are generally malleable-t...
    • Acids & Alkalis
      7th-class Science Chapter 17  
      An acid is a molecule or ion capable of donating a hydron (proton or hydrogen ion H+), or, alternatively, capable of forming a covalent bond with an electron pair (a Lewis acid). The first category...