1. Work in Electrical Systems
Chapter 2.3
Work in Electrical Systems

2. Forces in Electrical Systems
In an electrical system, forces are applied to charged objects by electric fields.
Electric fields are created by nearby charged objects.
As we learned in Ch. 1, potential difference is the prime mover in electrical systems. The presence of a potential difference can result in a charge moving and doing work in an electrical system.

3. Work in an Electrical System
You can’t see the electron, so you can’t actually see work being done. You can only see, hear or feel the results of electrical work.
Rotation, such as the blades in a fan, light, sound and heat are all examples of the results of electrical work being converted into other forms of energy.

4. Calculating Electrical Work
Work is done in electrical systems by multiplying the potential difference in volts (V) by the charge moved in coulombs (C) . As always, the units for work will be joules (J).
The formula for electrical work is
Work (W) + potential difference (ΔV) x charge moved (q) OR
W = ΔV x q

5. Effects of Electrical Work
Electrical work is done when voltage results in charge movement. Electrical work produces movement, thermal energy, light and sound.
Electric motors can move fluids by driving pumps and fans. This can result in the work done in a fluid system.

6. Effects of Electrical Work - 1
Another effect of voltage causing electric charges to move is the production of thermal energy.
This production of thermal energy is used in devices such as heaters, clothes dryers, hair dryers and ovens.
Another effect of charge movement is the production of light. Common forms of light are incandescent bulbs, fluorescent bulbs, and lasers.

7. Effects of Electrical Work - 2
Other forms of light energy that may result from charge movement are radio waves, TV signals and microwaves. These are all forms of electromagnetic radiation.
Finally, movement of charges can result in sound waves being produced. This results from converting electrical work into mechanical work.

8. Why use Electricity to do Work?
Electricity is produced at generating stations using the following process:
Coal, gas or oil are burned to produce thermal energy.
Thermal energy is used to convert water into steam.
Steam pressure is used to turn turbines.
Turbines drive electrical generators, which, in turn, produce electricity.

9. Reasons or Using Electricity
Electricity is an affordable way to transport energy.
Electricity can move long distances through overhead or underground wires.
Electrical energy can be transformed into other forms of energy and work.
Electricity is convenient and easy to use and provides a ready source of energy.