SC 6.1

• Source of energy

  1. Renewable energy
  2. From living things -- biomass
  3. From non-living things -- sun, water, wind, wave, tide, geothermal
  4. Non-Renewable energy
  5. Fossil fuel -- Petroleum, Natural gas, Coal
  6. Non-fossil fuel -- Radioactive material
• Renewable energy sources

  A source of energy whose supply is continuous, can be replaced and cannot be depleted
• Non-renewable energy sources

  A source of energy that cannot be replaced and can be depleted
• Electricity

  • The phenomena associated with the presence and motion of electric charge
• Magnetism

  A force that can repel or attract objects that have a magnetic material like iron
• Electrical energy generators

  • A generator is a tool used to convert mechanical energy into electricity
  • Electricity is generated using the principle of electromagnetic induction
  • The induction current is generated when a conductor wire coil moves while cutting the magnetic field lines
  • Induction current is generated by relative motion between wire coil and magnet
  • The type of induction current generated at electric power station is alternating current
• Process of generating electricity

  Movement of the wire

  • Which causes the magnetic field lines to be cut
  • A connecting wire or solenoid is moved rapidly through the space between the magnetic poles as shown in diagram
  • An induced current is produced in the connecting wire or solenoid, and it flows through the galvanometer
  • The pointer in the galvanometer deflects

  
• Process of generating electricity

  Movement of the magnet

  • Which causes the magnetic field lines to be cut
  • A magnet is moved as shown in diagram so that the magnetic field lines are cut by the connecting wire or solenoid
  • An induced current is produced in the connecting wire or solenoid, and it flows through the galvanometer
  • The pointer in the galvanometer deflects

  
• • Various energy source used to generate electrical energy
  • Source of energy can be divided into two groups
  • Renewable energy
  • Non-renewable energy
• Renewable energy source

  • Energy source that can be replaced and cannot be depleted
  • Examples:
  • wind energy
  • Biomass energy -- Sabah
  • Geothermal energy
  • Hydro energy -- Bakun
  • Wave energy
  • Tidal energy -- Pulau Perhentian
  • Solar energy -- Pulau Perhentian
• Non-renewable energy source

  • Energy source that cannot be replaced and can be depleted
  • Examples:
  • Coal
  • Nuclear energy
  • Natural gas -- Negeri Sembilan
  • Petroleum such as diesel
• Thermal generator (Non-renewable generator)

  1. Burning of fuel, natural gas or coal
  2. Water is boiled to turn into steam at high temperature
  3. Steam at high pressure rotates turbine
  4. Generator is rotated to produce electrical energy

  Energy change

  1. Chemical energy
  2. From petroleum or natural gas
  3. Heat energy
  4. Steam consist of heat energy
  5. Kinetic energy
  6. Kinetic energy turns turbine
  7. Electric energy
  8. Electric energy produced by dynamo

  
• Solar generator (Renewable generator)

  1. Light from the Sun's ray are absorbed by solar cells in solar panels
  2. Solar cells convert light into electrical energy

  Energy change

  1. Light energy
  2. From Sun
  3. Electric energy
• Hydroelectric generator (Renewable generator)

  1. Water stored in high reservoir flows out
  2. Water flows from high level to low level
  3. Swift flow of water rotates turbine
  4. Generator is rotated to produce electrical energy

  Energy change

  1. Gravitational potential energy
  2. Water reserve in the dam consist of this energy
  3. Kinetic energy
  4. Kinetic energy from water fall turns the turbine
  5. Electrical energy
  6. Electric energy produced by dynamo

  
• Wind turbine (Renewable generator)

  1. Moving air or wind
  2. Wind rotates blade
  3. Blade rotates turbine
  4. Generator is rotated to produce electrical energy

  Energy change

  1. Kinetic energy
  2. Moving air
  3. Electric energy
  4. Electric energy produced by dynamo
• Nuclear generator (Non-renewable generator)

  1. Nuclear reaction in nuclear reactor
  2. Water is boiled to turn into steam at high pressure
  3. Steam at high pressure rotates turbine
  4. Generator is rotated to produce electrical energy

  Energy change

  1. Nuclear energy
  2. Fusion of radioactive in nuclear reactor
  3. Heat energy
  4. Released from nuclear energy
  5. Kinetic energy
  6. Kinetic energy turns turbine
  7. Electric energy
  8. Electric energy produced by dynamo

  
• Biomass generator (Renewable generator)

  1. Combustion of methane produced by biomass
  2. Water is boiled to turn into steam at high pressure
  3. Steam at high pressure rotates turbine
  4. Generator is rotated to produce electrical energy

  Energy change

  1. Chemical energy
  2. From biomass
  3. Heat energy
  4. Released from combustion of methane
  5. Kinetic energy
  6. Kinetic energy turns turbine
  7. Electric energy
  8. Electric energy produced by dynamo

  
• Wave power station (Renewable generator)

  1. Air pushed out of the chamber when the water level in the chamber rises
  2. Swift flow of air rotates turbine
  3. Generator is rotated to produce electrical energy

  Energy change

  1. Kinetic energy
  2. Potential energy
  3. Kinetic energy
  4. Kinetic energy turns turbine
  5. Electric energy
  6. Electric energy produced by dynamo

  
• Electric current is divided into two types

  1. Direct current (D.C.)
  2. Alternating current (A.C)
• Direct current (D.C.)

  • An electric current that flows in one direction only

  Example of device

  • Torchlight
  • Toy car
  • Calculator

  Example of generators

  • Solar cell
  • Accumulator
  • Batteries
• Alternating current (A.C.)

  • An electric current that flows in constantly reversing direction only

  Example of device

  • Bread toaster
  • Air conditioner
  • Hair dryer
• Cathode Ray Oscilloscope (C.R.O.)

  • An electronic device that is used to show the differences in the shape of graph, direction of current and voltage change for direct current and alternating current

  1. Y-gain knob
  2. To change the magnitude of the height of the light spot
  3. Y-shift knob
  4. To adjust the position of the light spot vertically
  5. X-shift knob
  6. To adjust the position of the light spot horizontally
  7. Direct current / Alternating current switch
  8. Selected according to the type of input received
• Cathode Ray Oscilloscope (C.R.O.)

  1. Intensity control knob
  2. To control the brightness of the light spot on the C.R.O screen
  3. Focus control knob
  4. To control the sharpness of the light spot on the C.R.O. screen
  5. Time-base knob
  6. To control the movement of the light spot which sweeps across the C.R.O. screen horizontally
• Solving problems related to electrical energy supply in life

  By using a biogas source to generate electricity

  1. Rural areas
  2. Biogas is a gas that is highly flammable and is produced when organic matter such as cow dung decays
  3. In a biogas generator, cow dung is collected and is placed into a biogas fermentation tank
  4. The biogas obtained is used to run a generator in a combustion engine to produce electricity
• Solving problems related to electrical energy supply in life

  By building a hydroelectric generator in a river

  • Power station that use river water to generate power depend on the rapidity of the water flowing through the river
  • Therefore, watermills are built across a rapidly flowing river
  • The water will turn the turbine which is turn spins the dynamo, electricity is generated