Speaker: Glenn MossyBiography: Glenn has forty years of taking things apart and building new things, with a special interest in all things robotics. In his home hackerspace, Glenn currently is building a number of Arduino based shields for robotics and enjoys introducing others to the fun of electronics. Thirty years ago he gave his first presentation on motor-control for robotics at a conference with the International Association of Science and Technology for Development (IASTED). Glenn holds a bachelors degree in Electrical Engineering from Louisiana Tech University (1986). Visit him and read his blog athttp://gmossy.wordpress.com
Hi My name is Glenn Mossy and I’m a maker, electronics hobbyist hacker. My grandpa gave me a Radioshack electronics 100 in 1 kit when I was 8.I buildnumber of Arduino based shields for robotics and enjoys introducing others to the fun of electronicsI am going to make 3 points in my talk.Point 1. Setting up your labPoint 2. Ohm’s LawPoint 3 Using Ohms law for Practical Use.
The fundamental units.What are the common voltage supplies for your experiments?How much current do these projects we are going to build need?All about Resistors.
This is a law that helps in the understanding of how voltage and opposition in a circuit affect current.It does not help in the determination of how a voltage is produced.It does not help in the determination of the factors affecting resistance.V = IR (current & resistance do not affect voltage)R = V/I (voltage & current do not affect resistance)
A battery is like the Water pump.Water Pump creates the potential and has a input and output.You want the water to flow once the hose circuit is completed.This creates your voltage.Water Flowing = Current Flow as in Current.
Using the original law in some AC circuits does not return the value of current, and the modified version does.impedance.” a measure of the opposition to time-varying electric current in an electric circuitWhen this law was ascertained by George Simon Ohm, the only circuit property known at the time was Resistance.I = E / R . . . . . Good only in resistive circuits!!Michael Faraday, John Henry and others later discovered Inductance and CapacitanceInductance and/or capacitance in an alternating current circuit also exhibit ‘Opposition” to circuit current. Z = (R2 +(XL - XC)2)To be able to use the Ohm’s Law concept in all circuits one must use I = E / Z . . . Good in all Circuits!
Q. What is the current through the resistor? I = V/RQ. What is the voltage across the resistor? V = I RQ. What is the resistance of the resistor? R = V/I
Summarize 3 points in my talk.Point 1. Setting up your labPoint 2. Ohm’s LawPoint 3 Using Ohms law for Practical Use.
ElectronicsTechnologyThe Importance of current, resistance, voltage & ohms law.HelpingYour Raspberry PI SurviveYouGlenn Mossygmossy@yahoo.com~June 2013Some Kind of User Group(SKUG)
Points I’m going to cover Ohms Law•Fundamental Units•Ohm’s Law•LED Resistor ExampleOhm’s Law Practical Use Example• Going Further with Ohms Law
Current shown Graphically!!6.24 x 1018 electronsConductorGiven Point1 CoulombRate of Electron flow(CURRENT) is1 Coulomb per second(1 AMPERE)1 C = 1 A x 1 second1 Coulomb moved . .
Ohm’s Law States that• The current is directly proportional to the voltage and indirectlyproportional to the resistance.
Hydraulic Analogy• Electricity might be compared to water:• A battery could be likened onto a water pump.• Voltage (V) or water pressure (pounds per square inch).• Current could be likened onto the flow rate of water.• Coulombs per second = Amperes (A) or gallons per minute.• A wire is analogous to a water hose.• Squeezing the hose is Resistance (R) on the water hose.• An open switch is like a closed valve . .
• Ohm’s original Law was determined when capacitance and inductance wasstill not studied in detail.• So that Ohm’s Law can be used in any circuit including Alternating currentcircuits:• Modification:• The current is directly proportional to the voltage and indirectlyproportional to the impedance.”Ohm’s Law then & now!
References• Wikipedia: http://en.wikipedia.org/wiki/Ohms_law• Circuitlab Website: https://www.circuitlab.com• Care and Feeding of LED’s: http://www.thebox.myzen.co.uk/Tutorial/LEDs.html• Spice Info: http://bwrcs.eecs.berkeley.edu/Classes/IcBook/SPICE/• Physics Classroom: http://www.physicsclassroom.com/Class/circuits/u9l3c.cfm• Experiments: http://www.juliantrubin.com/bigten/ohmlawexperiments.html• Ohm Unit: http://en.wikipedia.org/wiki/Ohm_(unit)
Georg Simon Ohm“Die galvanische Kette”Faraday1836Maxwell2nd Great Unification in Physics1879Kirchoff1845Henry1831Helmholtz1842Ohm’s Law’s ImportanceKleist & Muschenbrook1746Galvani1780Volta1800Fourier18221827