Basic Electricity

Learning OutcomeThe basic study of the principals of electricity

Objectives

• Describe the parts of an atom.• Explain conductors and Insulators• Define electrical terms• Demonstrate electrical color code• Describe and verify Ohms law

The Atom

• To understand electricity you must understand the atom.

• The Atom is made up of three main parts.– Protons– Electrons– Neutrons

Clipart by MS Clipart 2013

The Components

• Protons are at the center of the atom with a positive charge.

• The Neutrons are also at the center of the atom with neither a negative or positive charge.

• The Electrons are attracted to the protons and create an orbit around them with a negative charge

The Principal

• Because the electrons are positive and the protons are negative they are attracted to each other.

• The energy located in the electrons is called the electromotive force and keeps the electron in motion in orbit around the center.

• The charge is the characteristic of a material that enables it to exert force on another material.

Electric Flow

• The flow of electrons occurs when a conductor has a negative voltage connected to one end and a positive connected to the other end.

• Conductors allow electricity to flow freely while insulators restrict or inhibit the flow electricity.

Conductors and Insulators

• Conductors- metals make great conductors– Gold– Copper– Tin– Silver

• Insulators- Non-metals make great insulators– Glass– Rubber– Plastics

Conductors and Insulators

• Copper allow the electricity to flow while the plastic insulator keeps the electricity in

Current

• Current flows in a loop from negative to positive.

Types of Current

• AC(Alternating Current)- Alternating current flows from 0v to a Positive peak value to a negative peak value overtime. Powers our homes and offices through the wall

• DC(Direct Current)- Direct Current has a consistent and steady positive voltage over time. Powers our cars, flashlights and cell phones through batteries.

DC-Direct Current

AC-Alternating Current

Terms

• Volt• Amp• Current• Resistors• Watts• Ohms• Capacitors• Inductors• Transformers• Grounding

Terms

• Volts - is the unit of measure for the voltage of a circuit

• Amp - is the unit of measure for the current of a circuit.

• Current - is the flow of electron in a circuit.

• Resistors - Provide opposition to the flow of electrons in a circuit.

Terms

• Watts - is the amount of power or work a circuit is using.

• Ohms - is the unit of measure for resistance.

• Capacitor - Stores electricity• Inductor - Resists changes in current• Grounding - Diverts unwanted or

unused electricity.

Resistors-Color Code

  Digit Multiplier   Tolerance

Black 0 1 10^0 1%

Brown 1 10 10^1 2%

Red 2 100 10^2 3%

Orange 3 1000 10^3 4%

Yellow 4 10000 10^4  

Green 5 100000 10^5  

Blue 6 1000000 10^6  

Violet 7 10000000 10^7  

Grey 8 100000000 10^8  

White 9      

Gold   0.1   5%

Silver   0.01   10%

None       20%

Resistor-Value

• What is the Value?

Resistor-Value

• Value 22000000 Or 22Meg Ohms

Resistor-Value

• What is the Value?

Resistor-Value

• Value 4100 or 4.1K Ohms

Ohms Law

V= I x R

Voltage (V) or (E)

• Can be found with:

• V=IxR• V= P/I• The square root of (RXP)

Current (I)

• Can be found with:

• P/V• V/R• Square root of (P/R)

Resistance (R)

• Can be found with:

• V/I• V^2/P• P/I^2

Power (P)

• Can be found with:

• VxI• RxI^2• V^2/R

Series- Circuit

Parallel Circuit

Electrical Switches

• Toggle• Slider• Dip• Rotary

Power Problems

• Surge• Over Voltage • Under Voltage• Brownouts • Spikes• Sags

Power Problems

• Surge - A large boost of electricity at least 15-20% above the rated amount.

• Spike - A very large as high as 10000 volts

• Sag - A drop in the total voltage that can last up to a couple of minutes.

• Brownout - A stress on a power brought on usually by hot or cold spells. Can sometimes last for days.

Grounding

• Grounding is necessary to provide a direct path for excess electrical current.

Questions

• Michael Harsh Mharsh@collin.edu

All graphics were created by Mike Harsh and used with permission unless otherwise noted.

This material is based upon work supported by the National Science Foundation under Grant No. 1205077 and Grant No. 0903239. Any opinions, findings and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation.