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Pre-Class Monday 10-22-12. What do you think an Electrical Engineer does?. Electrical Engineering. The world's leading professional association for the advancement of technology. Electrical Specifics. The most common/populated engineering field
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Pre-Class Monday 10-22-12 What do you think an Electrical Engineer does?
Electrical Engineering The world's leading professional association for the advancement of technology
Electrical Specifics • The most common/populated engineering field • Responsible for the design, development, testing, and supervision of the manufacture of electrical equipment (from household appliances to satellite systems) • Any product that has electricity falls under their “jurisdiction” • Main areas: Power generation, transmission, and distribution; communications; computer electronics; electrical equipment manufacturing
Pre-Class Tuesday 10-23-12 Why is Electrical Engineering so important to everyday life?
8 Major Categories • Computers Computer Engineering branch • Communications Global Positioning Systems (GPS), fiber optics, and lasers • Circuits and solid-state devices making electronic devices smaller and more efficient • Control reliable, efficient, and safe electronics • Instrumentation measuring how an electronic device is performing as compare to its specs • Signal processing filtering, amplifying, and modifying any signal (digital or otherwise) • Bioengineering non-invasive techniques (Magnetic Resonance Imaging, MRI, or Computer Automated Tomography, CAT, scan) • Power the most traditional of them all, electrical power
Making a Testing Apparatus • Objective • Design and construct a battery holder. • Materials • Index card ■C-cell battery • 2 paper clips ■10 cm of masking tape • Procedures • Design a battery holder for a C-cell that allows for connection to wires on both sides. • Use materials to construct it. • Use your testing apparatus in the following lab.
Pre-Class Wednesday 10-24-12 What is the word in black? If it were resting on a mirror or a light were behind it to cast a shadow below it, what would it read?
INSULATOR charges do not flow freely impedes electricity CONDUCTOR charges flow freely allows electricity to flow through it CONDUCTIVE MATERIALS NOTE: Wood is not a good conductor nor insulator.
Objectives To determine what conducts electricity Materials Wires Light bulbs Procedures Divide into groups of 2 or 3. Obtain materials from cart. Test 8-10 items. C-cell Battery Other? Insulation vs. Conduction
Pre-Class Thursday 10-25-12 If 5 cats can catch 5 rats in 5 minutes, how many cats do you need to catch 100 rats in 100 minutes? 5
The largest, most prominent engineering field • Aerospace • Antenna • Broadcast • Communications • Computer • Control Systems • Lasers • Power • Robotics • Signal Processing • Wireless Starting salary in 2011: $61,420 (BS), $72,340 (MS), $88,970 (PhD) Average salary in 2005: $51,773
CURRENT • The flow of positive charges (in theory) • The flow of negative charges (in real life) • A river of electrical energy that moves through a wire • Must have a closed continuous loop to work
Current number of charges that travel per second Battery voltage (source) Resistance impedes current uses energy Ammeter measures current Voltmeter measure voltage Measured in Amperes Amps or A Measured in Volts Volts or V Measured in Ohms ohms (W) Measures Amps Measures Volts VOCABULARY VOCABULARY http://regentsprep.org/Regents/physics/phys03/bsimplcir/default.htm
Schematics • A sketch of what the circuit looks like • Represents how the current will flow in the circuit • Specific types of symbols for sketches
Pre-Class Friday 10-26-12 • Draw and label a circuit with the proper schematic symbols containing a battery, a resistor, and a switch.
PARALLEL current has multiple paths to follow broken circuit may not stop electrical flow voltage is the same through each resistor current adds for each SERIES current has only one path to follow broken circuit stops all flow of electricity current is the same through each resistor voltage adds for each CIRCUITS http://www.regentsprep.org/Regents/physics/phys03/bparcir/default.htm http://www.regentsprep.org/Regents/physics/phys03/bsercir/default.htm
Schematics Lab • Objective • Construct two simple circuits. • Draw schematics of simple circuits. • Materials • Battery holder ■C-cell battery • Wires ■ Voltmeter • 2 light bulbs ■ Ammeter • Procedures • Construct a simple series circuit. • Measure and record the current and voltage through the light bulb. • Draw a schematic of the series circuit. • Construct a simple parallel circuit. • Measure and record the current and voltage through each light bulb. • Draw a schematic of the parallel circuit. • Questions • The ammeter was to be wired in series. Explain why. • The voltmeter was to be wired in parallel. Explain why. • For a circuit to work (assuming you have power and proper equipment), what is vital?
Pre-Class Monday 10-29-12 • At the recent web developer's bowling match, two games were played. Kev beat Stuart in both games, also Richard beat John in both games. The winner in game 1 came second in game 2. Richard won game 2 and John beat Stuart in game 1. No player got the same placing twice. Can you determine who finished where in each game? Name #1 #2Kev 1 2Richard 2 1John 3 4Stuart 4 3
OHM’S LAW • Ohm defined how current(amps), voltage(volts), and resistance(ohms=W) relate V =IR • V : voltage of battery (e.g. 9 V battery) • I : current (number of charges per second) • R : resistance (e.g. light bulb, stereo, etc.)
Electrical Power P = I2 R = V2/ R = IV P : power (Watts) I : current (Amps) R : resistance (W) V : voltage (Volts) Remember: Power is energy per time (P=E/t)
PARALLEL current has multiple paths to follow 1/Requivalent = 1/R1 + 1/R2 voltage is the same Vtotal = V1 = V2 current adds for each Itotal = I1 + I2 SERIES current has only one path to follow Requivalent = R1 + R2 voltage adds for each Vtotal = V1 + V2 current is the same Itotal = I1 = I2 CIRCUITS http://www.regentsprep.org/Regents/physics/phys03/bparcir/default.htm http://www.regentsprep.org/Regents/physics/phys03/bsercir/default.htm
Pre-Class Tuesday 10-30-12 • What is Ohm’s Law?
Incandescent A piece of metal in a closed space is heated by electricity Filament (glowing metal) made of tungsten Fluorescent An electric current is sent through a gas (mercury and argon) in a closed space Similar to lightning Producing Light All artificial producers of light follow one of these two methods, except for a laser or LED.
Lightning (and electrical) Safety • Lightning • Attracted to tall, pointy conductors • Safest place: car • Beware of storing charge accidently • Always switch off the breaker before working on wires in the home.
Ohm’s Lab • Materials • 1.5 V battery • 4 sets of wires • Ammeter • Voltmeter • 2 light bulbs • Switch • Objectives • To explore how to wire a circuit correctly • To use Ohm’s Law in calculations • To practice drawing schematics
Procedures • Determine the voltage of your battery. Record its values. • Connect the 1.5 V battery to the light bulb and switch. Measure the current through the circuit (ammeter) and the voltage drop across the light bulb (voltmeter). Record their values. • Draw a schematic of step 2. • Add another light bulb to the circuit (series). Measure the current through the circuit and the voltage drop across both light bulbs. Record their values. • Draw a schematic for step 4. • Repeat steps 4 and 5 with the light bulbs being in parallel. • The 6 V battery provides too much energy for the light bulbs for an extended time. Using the resistors provided and the knowledge gained already, make a stable circuit to provide a bright, long-lasting bulb. • Draw a schematic for step 7. • Measure the current through and the voltage drop across each resistor and light bulb. Record their values. • Find the resistance of each light bulb and resistor for every step. Record their values.
Table • Questions: • What happens to the current in a series circuit? Parallel? • What happens to the voltage in a series circuit? Parallel?
Pre-Class Friday 11-2-12 • There are four ways to change the internal resistance of a wire. Give me one of them.
Pre-class Monday 11-5-12 A 1.5 Volt battery is connected to a small light bulb with a resistance of 9 W. What is the current in and power used by the bulb? V=IR I = V/R = 1.5 / 9 = 1/6 or 0.167 Amps P=IV P = I V = 0.167 x 1.5 = 0.25 Watts
Getting started in Solid Edge Solid Edge Fundamentals ST4
Solid Edge Environments: Part Sheet Metal Part Weldment Assembly Draft Start Programs Solid Edge V20
Schematics in Solid Edge ST4 • Solid Edge is a 2D and 3D Computer Aided Design (CAD) program. • Solid Edge allows you to take hand sketches and turn them into professional drawings. • The draft environment will produce 2D drawings. • Using the Ohm’s Law Lab from this week, draw one of the schematics in Solid Edge and show it to me. Each person in the group has to draw one. • I will check your name off the paper when you have completed the schematic. Be sure to turn in the paper when everyone is done.
Pre-class Monday 4-2-12 Write: “Reviewing for written test” or “Finishing performance test”.
Pre-class Tuesday 4x3=12 Write: “Written and performance test today.”
Pre-class Thursday 10-23-08 Guest Speaker: Adam Panagos
Pre-Class Friday 03-14-08 Ifpwere a shape, what shape would it be? HappypDay!
Pre-Class Tuesday 10-11-11 Today’s date is a binary number. What would be the decimal (base 10) value for it? 47