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Energy - Coggle Diagram
Energy
Definition of Energy
Capacity to do work
Scalar quantity
SI unit: Joule (J)
Forms Of Energy
Kinetic Energy (energy of motion)
Potential Energy (energy due to position)
Thermal Energy
Chemical Energy
Electrical Energy
Nuclear Energy
Light (Radiant) Energy
Sound Energy
Transformation of Energy
Energy can change from one form to another
Examples:
Electric → Light (bulb)
Chemical → Mechanical (engine)
Energy converters/devices
Law of Conservation
Energy cannot be created or destroyed
Total energy remains constant
Can only be transformed
Work and Energy
Work done = Energy transferred
Work = Force × Displacement (in direction of force)
SI Unit of Work: Joule
Power and Energy
Power = Rate of doing work or transferring energy
Power = Work done / Time
Unit: Watt (W)
Kilowatt-hour (kWh) – unit of energy used in homes
1 kWh = 3.6 × 10⁶ J
Mechanical Energy
Sum of Kinetic + Potential Energy
In absence of friction, total mechanical energy is conserved
Potential & Kinetic Energy
Potential Energy = mgh (mass × gravity × height)
Kinetic Energy = ½mv² (½ × mass × velocity²)
Applications of Energy
Machines
Electricity generation
Transport
Heating and Cooling
Renewable and Non-Renewable Energy
Renewable: Solar, Wind, Hydro, Biomass
Non-renewable: Coal, Oil, Natural Gas
Environmental impact of energy use