Electricity & Magnetism Road Map Review

TSW describe the interactions of like and unlike charges.
TSW compare and contrast parallel and series circuits.
TSW compare and contrast insulators and conductors. Electricity & Magnetism Unit Electric Charge & Magnetism
(Pages 9-10 & 81) •Particles have the same type of charge – positive or negative – have like charges and particles with different charges have unlike charges.

•Particles with like charges repel each other (or push away)

•Particles with unlike charges attract to each other (or pull together-opposites attract)

Seen with static electricity

The force exerted by a magnet. This force is not evenly distributed. Magnetic poles are the parts of the magnet where magnetism is the strongest.

As with charges, opposite poles attract and like poles repel. Circuits & Parts of a Circuit
(Pages 43 - 44) Circuit - A closed path through which a charge can flow


1. Voltage Source = battery
2. Conductor = wire
3. Switch = open and closes the circuit
4. Electrical device (resistor) = object that needs power


The wire cover is the insulator; it is made of plastic. The wire is the conductor; it provides a path through which a charge can flow.


Conductor - Something that transfers electricity easily

Examples: iron, steel, copper, aluminum, water, humans, graphite (pencil lead)


Insulator- Something that does not transfer electricity easily

Examples: plastic, rubber, Styrofoam, glass, dry wood


Resistor - An electrical device that slows the flow of a charge. Parts of a Circuit (continued)
(Pages 46 - 49) Short Circuit - These may occur because current follows the path of least resistance, and we usually don’t want it to follow this path!

Grounding - This provides a harmless, low-resistance path for electricity to follow. A lightning rod is an example.

Fuses and Circuit Breakers - Keep us safe by opening the circuit (turning the object off). Series Circuit
(page 52) The current follows a single path; the charge coming from the battery flows first through one light bulb, then the next light bulb, and the next light bulb.

Advantage -
1.Very little wire is used

Disadvantage -
1.Everything must be working for it to function.
2.If one bulb goes out, they ALL go out.
3.The more light bulbs that are added, the less current there is and bulbs aren’t as bright. Magnets attract iron and steel. fuse circuit
breaker Parallel Circuit (Page 53) The current follows more than one path; each path is called a branch. Most homes and businesses are connected in parallel.

Advantages -
1.If one bulb burns out, the other bulbs will continue to work.
2.Each bulb added has its own branch to the power source, so the bulbs burn at their brightest.

Disadvantage -
1.Require more wire than a series circuit