PS.11 Electricity & Magnetism (2024)

Several factors affect how much electricity can flow through a system.
Resistance is a property of matter that affects the flow of electricity. Some substances have more resistance than others.

Friction can cause electrons to be transferred from one object to another.
- These static electrical charges can build up on an object and be discharged slowly or rapidly.
- This is often called static electricity.

Electricity is related to magnetism.
Magnetic fields can produce electrical current in conductors.
- Electricity can produce a magnetic field and cause iron and steel objects to act like magnets.
- Electromagnets are temporary magnets that lose their magnetism when the electric current is removed.
Both a motor and a generator have magnets (or electromagnets) and a coil of wire that creates another magnetic field.
- A generator is a device that converts mechanical energy into electrical energy.
- Most of the electrical energy we use comes from generators.
- Electric motors convert electrical energy into mechanical energy that is used to do work.
- Examples of motors include those in many household appliances, such as blenders and washing machines.

A conductor is a material that transfers an electric current well.
An insulator is material that does not transfer an electric current.
A semiconductor is in-between a conductor and an insulator.
The diode is a semiconductor device that acts like a one way valve to control the flow of electricity in electrical circuits.
- Solar cells are made of semiconductor diodes that produce direct current (DC) when visiblelight, infrared light (IR), or ultraviolet (UV) energy strikes them.
- Light emitting diodes (LED) emit visible light or infrared radiation when current passes through them.
- An example is the transmitter in an infrared TV remote or the lighting course behind the screen in an LED TV or notebook computer screen.
Transistors are semiconductor devices made from silicon, and other semiconductors.
- They are used to amplify electrical signals (in stereos, radios, etc.) or to act like a light switch turning the flow of electricity on and off .

design an investigation to illustrate the effects of static electricity.
construct and compare series and parallel circuits.
construct simple circuits to determine the relationship between voltage, resistance, and current.

provide examples of materials that are good conductors, semiconductors, and insulators.
identify current applications of semiconductors and their uses (e.g., diodes and transistors).