Electricity and Electronics Technology Education Dept. Bellwood-Antis Middle School Mr. Mackereth.
-
date post
21-Dec-2015 -
Category
Documents
-
view
213 -
download
0
Transcript of Electricity and Electronics Technology Education Dept. Bellwood-Antis Middle School Mr. Mackereth.
WHAT IS ELECTRICITY?
• ELECTRICITY is the FLOW of ELECTRONS through a current carrying CONDUCTOR or WIRE.
• ELECTRICITY CAN BE MEASURED AS…..• AMPERAGE (AMPS)- The electron’s RATE OF FLOW• VOLTAGE (VOLTS)- The PRESSURE of the electrons• POWER (WATTS)-The measure of POWER OUTPUT• RESISTANCE (OHMS)- The friction in the electric
wire while electricity is trying to pass through.
COMMOM ELECTRICAL TERMS:
• POTENTIAL ENERGY- Energy in position, or stored energy. At rest, ready to release energy
• KINETIC ENERGY- Energy in motion, or energy being consumed or used to do work.
• MATTER- Object(s) that occupy space (atom)• MOLECULE- the smallest part of a compound.• ATOM- The individual elements that make up
compounds in our world. ALL MOLECULES ARE MADE FROM INDIVIDUAL ATOMS!
WHAT ARE SOME OF THE DIFFERENT WAYS OUR SOCIETY USES ELECTRICITY?
• HOUSEHOLD USES
• MANUFACTURING
• COMMUNICATION
• RECREATION
• HEALTH & MEDICAL
• PUBLIC LIGHTING
• SAFETY & SECURITY
• PROFESSIONAL USES
• TEMPERATURE CONTROLS
• RESEARCH / LABORATORY
COMMOM ELECTRICAL TERMS:• PROTONS- A positively charged particle in an atom• ELECTRONS- Negatively charged particle in an atom• DIRECT CURRENT (DC)- A continuous electrical
energy, usually from transformers and batteries• DC electric power ALWAYS flows from positive to negative• ALTERNATING CURRENT (AC)- Electricity in a wave
form that pulses from + to – 60 times a second.• Regular household/business electric power is AC• AC electricity pulses back & forth b/w positive & negative
COMMOM ELECTRICAL TERMS:
• CONDUCTOR- An object that WILL allow electric current to flow through itself. (PLASTIC, RUBBER, PVC)
• INSULATOR - An object that WILL NOT allow electric current to flow through itself. (WATER & METALS)
• ELECTRICITY QUIZ #1 IS TOMORROW!• INCLUDES EVERYTHING FROM PAGE 1 OF NOTES.
ALSO, KNOW SOCIETY’S USES OF ELECTRICITY!• BE ABLE TO DESCRIBE DIFFERENCES BETWEEN
ELECTRICAL TERMS USING COMPLETE SENTENCES.
TYPES OF CIRCUITS• OPEN CIRCUIT- An electric pathway that is not
connected, or has a break (short) in the path.
• ELECTRICITY WON’T FLOW IN AN OPEN CIRCUIT
• A light switch in the OFF position is an OPEN circuit
• CLOSED CIRCUIT- An COMPLETE electrical pathway
• ELECTRICITY WILL FLOW IN A CLOSED CIRCUIT
• A light switch in the ON position is a CLOSED circuit
TYPES OF CIRCUITS• SERIES CIRCUIT- A path with only ONE “HOT” WIRE.• Devices in a series circuit are connected one after the
other. Old Christmas lights are wired IN SERIES.• PARALLEL CIRCUIT- A path containing TWO WIRES
(one HOT & one NEUTRAL wire.) Each device is connected to BOTH WIRES. Homes are IN PARALLEL
• GROUNDED CIRCUIT- a safe circuit preventing shock• Make sure you can identify the 18 different
electrical symbols on your FLASH CARDS.
ELECTRICITY QUIZ #2• INCLUDES EVERYTHING FROM PAGES 1
& 2 OF YOUR NOTES. ALSO KNOW THE FIVE DIFFERENT CIRCUITS!• BE ABLE TO DEFINE ALL THE TERMS &
BE ABLE TO IDENTIFY ALL 18 SYMBOLS
• THE QUIZ IS TOMORROW!
CALCULATING ELECTRICAL VALUES
• Scientists discovered in the 19th century that electricity follows the laws of physics & can be calculated using mathematical equations.
• KNOW THE FORMULAS BELOW:• WATTS = VOLTS x AMPS (W = V x A)• VOLTS = AMPS x RESISTANCE (V = A x R)• If you know or are given any two of the four
values, YOU CAN CALCULATE THE OTHERS!
PRACTICE PROBLEMSPROBLEM #1
• Volts = 120 Amps = 3• FIND WATTS & OHMS• W = V x A • W =120 X 3 • W = 360
• V = A x R• 120 = 3 X R
3 3• R = 40
PROBLEM #2• Volts = 120 Watts = 60
• FIND AMPS & OHMS• W = V x A • 60 =120 X A 120 120 • A = 0.5
• V = A x R• 120 = 0.5 X R
0.5 0.5• R = 240
PRACTICE PROBLEMSPROBLEM #3
• Volts = 12 Ohms = 24• FIND AMPS & WATTS• V = A x R• 12 = 24 X R
24 24• A= 0.5
• W = V x A• w = 12 X 0.5 • W = 6
PROBLEM #4• Watts = 1200 Amps = 15• FIND VOLTS & OHMS• W = V x A• 1200 = V X 15 15 15 • V= 80
• V = A x R• 80 = 15 X R
15 15• R = 5.33333333 (5.3)
HOMEWORKPROBLEM #1
• Volts = 240 Amps = 3• FIND WATTS & OHMS• W = V x A • W =240 X 3 • W = 720
• V = A x R• 240 = 3 X R
3 3• R = 80
PROBLEM #2• Volts = 120 Watts =
180• FIND AMPS & OHMS• W = V x A • 180=120 X A 120 120 • A = 1.5
• V = A x R• 120 = 1.5 X R
1.5 1.5• R = 280
RESISTORS• RESISTORS are man-made components that are
designed to limit the flow of electricity through small circuit boards and other electronic devices.
• RESISTORS have a FOUR COLOR CODE that tells us the size (amount of resistance) in each resistor.
• COLOR BAND #1- The 1st digit in the resistor size• COLOR BAND #2- The 2nd digit in the resistor size• COLOR BAND #3- # of zeros added (multiplier)• COLOR BAND #4- The TOLERANCE level allowed
PRACTICE PROBLEM 1, a resistor withRED YELLOW BROWN SILVER 2 4 add 1 zeros 10%ANSWER: 240 Ohms with a tolerance of 10%
• HIGH TOLERANCE• # of Ohms X 100 + T%
• 240 Ohms X 110%
• Answer: 264 Ohms
• LOW TOLERANCE• # Ohms X 100 + T%
• Ohms X 110%
• Answer: 216 Ohms
PRACTICE PROBLEM 2, a resistor withBROWN RED ORANGE GOLD 1 2 add 3 zeros 5%ANSWER: 12,000 Ohms with a tolerance of 5%
• HIGH TOLERANCE• # of Ohms X (100 + T %)
• 12,000 Ohms X 105%
• ANSWER: 12,600 Ohms
• LOW TOLERANCE• # Ohms X (100 – T %)
• 12,000 Ohms X 95%
• Answer: 11,400 Ohms
HOMEWORK #1 is a resistor with …. RED RED ORANGE SILVER 2 2 add 3 zeros 10%ANSWER: 22,000 Ohms with a tolerance of 10%
• HIGH TOLERANCE• # Ohms X (100 + T %)
• 22,000 Ohms X 110%
• ANS: 24,200 Ohms
• LOW TOLERANCE• # Ohms X (100 - T %)
• 22,000 Ohms X 90%
• ANS: 19,800 Ohms