To explain the energy flow through steady-state systems such as a filament lamp, a power station, and a vehicle traveling at a constant speed on a level road, I will provide a verbal description of the energy conversions and then illustrate the energy flow diagrams.
1. Filament Lamp (Light Bulb)
A filament lamp is an electrical device that converts electrical energy into light and heat energy. When electricity flows through the filament, the filament heats up and glows, emitting light. Some of the energy is lost as heat.
Energy Flow in a Filament Lamp:
- Electrical Energy is supplied to the filament lamp through wires.
- The filament heats up due to electrical resistance, converting the electrical energy into heat energy.
- A portion of the energy is also converted into light energy (visible light), but not all the electrical energy is transformed into useful light.
Energy Flow Diagram for a Filament Lamp:
2. Power Station (Thermal Power Plant)
A thermal power station typically burns fossil fuels (such as coal, natural gas, or oil) to generate electricity. The process involves converting chemical energy from the fuel into heat energy, which is used to generate steam. The steam drives a turbine, which produces mechanical energy, and this is further converted into electrical energy by a generator.
Energy Flow in a Power Station:
- Chemical Energy from the fuel (e.g., coal) is burned, releasing heat energy.
- The heat energy is used to boil water and produce steam.
- The steam drives a turbine, converting the heat energy into mechanical energy.
- The mechanical energy of the turbine is converted into electrical energy by a generator, which is then distributed.
Energy Flow Diagram for a Power Station:
3. Vehicle Traveling at Constant Speed on a Level Road
For a vehicle moving at a constant speed on a level road, energy is required to overcome frictional forces (like air resistance and rolling resistance) and maintain the motion. The vehicle’s engine uses chemical energy from fuel (e.g., gasoline or diesel) and converts it into mechanical energy to propel the vehicle forward. Some of the energy is also converted into heat, and frictional forces dissipate energy.
Energy Flow in a Vehicle:
- Chemical Energy in the fuel (gasoline or diesel) is converted into mechanical energy by the engine.
- The mechanical energy is used to overcome frictional forces (like air resistance and rolling resistance) and maintain the vehicle’s motion.
- Some energy is lost as heat energy due to internal friction and the exhaust gases.