Pre-Class Monday 10-22-12

What do you think an Electrical Engineer does?

Electrical EngineeringElectrical Engineering

The world's leading professional association for the advancement of technology

Electrical SpecificsElectrical 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 Categories8 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?

CONDUCTIVE MATERIALS

INSULATOR charges do not flow

freely impedes electricity

CONDUCTOR charges flow freely allows electricity to

flow through it

NOTE: Wood is not a good conductor nor insulator.

Insulation vs. Conduction 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?

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 ()

Measures Amps

Measures Voltshttp://regentsprep.org/Regents/physics/phys03/bsimplcir/default.htm

A sketch of what the circuit looks like

Represents how the current will flow in the circuit

Specific types of symbols for sketches

Schematics

Pre-Class Friday 10-26-12Pre-Class Friday 10-26-12

Draw and label a circuit with the proper schematic symbols containing a battery, a resistor, and a switch.

CIRCUITS 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

http://www.regentsprep.org/Regents/physics/phys03/bsercir/default.htm http://www.regentsprep.org/Regents/physics/phys03/bparcir/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  #2

Kev       1   2Richard   2   1John      3   4Stuart    4   3

OHM’S LAW

Ohm defined how current(amps), voltage(volts), and resistance(ohms=) relate

V = I R 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 PowerElectrical Power

P = I2 R = V2/ R = I VP : power (Watts)

I : current (Amps)

R : resistance ()

V : voltage (Volts)

Remember: Power is energy per time (P=E/t)

CIRCUITS 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

http://www.regentsprep.org/Regents/physics/phys03/bsercir/default.htm http://www.regentsprep.org/Regents/physics/phys03/bparcir/default.htm

Pre-Class Tuesday 10-30-12

What is Ohm’s Law?

Producing LightIncandescent 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

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

Procedures1. Determine the voltage of your battery. Record its values.2. 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.

3. Draw a schematic of step 2.4. 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.

5. Draw a schematic for step 4.6. Repeat steps 4 and 5 with the light bulbs being in parallel.7. 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.

8. Draw a schematic for step 7.9. Measure the current through and the voltage drop across each

resistor and light bulb. Record their values.10. Find the resistance of each light bulb and resistor for every step.

Record their values.

Table

Step V1 ( ) V2 ( ) I1 ( ) I2 ( ) R1 ( ) R2 ( )

2

4

6

9

Questions:

1) What happens to the current in a series circuit? Parallel?

2) 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 11-5-12A 1.5 Volt battery is connected to a small light

bulb with a resistance of 9 . What is the current in and power used by the bulb?

I = V/R = 1.5 / 9 = 1/6 or 0.167 Amps

P = I V = 0.167 x 1.5 = 0.25 Watts

Solid Edge Fundamentals ST4

Getting started in Solid Edge

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

If were a shape, what shape would it be?

HappyHappy Day!Day!

Pre-Class Tuesday 10-11-11

Today’s date is a binary number. What would be the decimal (base 10) value for it?