Transcript Electricity and Electronics - Bellwood

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
• PUBLIC LIGHTING
• MANUFACTURING
• SAFETY & SECURITY
• COMMUNICATION
• PROFESSIONAL USES
• RECREATION
• TEMPERATURE CONTROLS
• HEALTH & MEDICAL • 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 PROBLEMS
PROBLEM #1
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•
•
•
•
Volts = 120 Amps = 3
FIND WATTS & OHMS
W=VxA
W =120 X 3
W = 360
• V=A xR
• 120 = 3 X R
3 3
• R = 40
PROBLEM #2
•
•
•
•
Volts = 120
Watts = 60
FIND AMPS & OHMS
W=VxA
60 =120 X A
120 120
• A = 0.5
• V=A xR
• 120 = 0.5 X R
0.5 0.5
• R = 240
PRACTICE PROBLEMS
PROBLEM #3
• Volts = 12 Ohms = 24
• FIND AMPS & WATTS
• V=AxR
• 12 = 24 X R
24 24
• A= 0.5
• W=VxA
• w = 12 X 0.5
• W=6
PROBLEM #4
• Watts = 1200 Amps = 15
• FIND VOLTS & OHMS
• W=VxA
• 1200 = V X 15
15
15
• V= 80
• V=A xR
• 80 = 15 X R
15 15
• R = 5.33333333 (5.3)
HOMEWORK
PROBLEM #1
•
•
•
•
•
Volts = 240 Amps = 3
FIND WATTS & OHMS
W=VxA
W =240 X 3
W = 720
• V=A xR
• 240 = 3 X R
3 3
• R = 80
PROBLEM #2
•
•
•
•
Volts = 120
Watts = 180
FIND AMPS & OHMS
W=VxA
180=120 X A
120 120
• A = 1.5
• V=A xR
• 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 with
RED
YELLOW
BROWN
SILVER
2
4
add 1 zeros
10%
ANSWER: 240 Ohms with a tolerance of 10%
• HIGH TOLERANCE
• LOW TOLERANCE
• # of Ohms X 100 + T%
• # Ohms X 100 + T%
• 240 Ohms X 110%
• Ohms X 110%
• Answer: 264 Ohms
• Answer: 216 Ohms
PRACTICE PROBLEM 2, a resistor with
BROWN
RED
ORANGE
GOLD
1
2
add 3 zeros
5%
ANSWER: 12,000 Ohms with a tolerance of 5%
• HIGH TOLERANCE
• LOW TOLERANCE
• # of Ohms X (100 + T %)
• # Ohms X (100 – T %)
• 12,000 Ohms X 105%
• 12,000 Ohms X 95%
• ANSWER: 12,600 Ohms
• 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
• LOW TOLERANCE
• # Ohms X (100 + T %)
• # Ohms X (100 - T %)
• 22,000 Ohms X 110%
• 22,000 Ohms X 90%
• ANS: 24,200 Ohms
• ANS: 19,800 Ohms
HOMEWORK #2 is a resistor with ….
BROWN
RED
BROWN
SILVER
1
2
add 1 zero
10%
ANSWER: 120 Ohms with a tolerance of 10%
• HIGH TOLERANCE
• LOW TOLERANCE
• # Ohms X (100 + T %)
• # Ohms X (100 - T %)
• 120 Ohms X 110%
• 120 Ohms X 90%
• ANS: 132 Ohms
• ANS: 108 Ohms