Concise Selina Solutions for Class 8 Physics Chapter 8 Electricity


Electricity deals with topics related to electricity, photons and electrons. Electricity is nothing but a form of energy produced by charges. These charges that produce electricity can be at rest or moving. Electricity is the set of physical phenomena associated with the presence and motion of matter that has a property of electric charge. Electricity is related to magnetism, both being part of the phenomenon of electromagnetism, as described by Maxwell's equations.

  • Static Electricity. Static Electricity is nothing but the contact between equal amount of protons and electrons (positively and negatively charged subatomic particles). In order to make this friction work the particles are supposed to be of opposite nature (+,-). If two same-kind particles i.e. positive-positive or negative-negative, it would then be called as a ‘Non-friction’.
  • Current Electricity- Current Electricity is a flow of electric charge across an electrical field. This current is lead through a conductor. The conductors are generally of two types, Good and Bad conductors. Good conductors are the ones which let the electric charge flow through them (Copper wires) and the bad conductors are the ones which resists the electric charge (Wood). The constant flow of electric charge causes the conductor to heat up very often.
  • Hydro Electricity- Hydro Electricity is generated by harnessing the power of moving water. It is manufactured in large power generating stations using the same basic principle of a small grist mill yet on a much larger and vastly improved scale for better efficiency. Electrical generators are attached to huge turbine devices which spin at great speeds as a result of water rushing through them.
  • Solar Electricity- Solar Electricity is generated with the only power that has been in existence since the living breathed on this planet, the huge and singular source named as Sun. The sun rays are the only source in Solar Electricity. It is generated with the help of Photovoltaic (PV) technology by converting solar energy into solar electricity from sunlight. PV Systems use sunlight to power ordinary electrical equipments for example: household appliances, computers & lightings.