Section One Flashcards
What is AC
Alternating Current
Wall Outlet - put out AC you take AC from it
Can be converted
Switches directions, alternates it’s directions on a wire
What is DC
Direct Current
Battery - two sides + and -
Electronics
Can be converted plugging phone in charger. AC giving to charger can charger converts it to DC.
Move in one direction on the wire the whole time
Batteries plus and minus sign
What is terminal
- negative terminal
+ positive terminal
Terminal - Where electricity flows from in a battery
What is an open circuit
They do not work.
When only the negative terminal is connected to the device and not the positive terminal
What is a closed circuit?
When the negative terminal goes through the object and has a path to the positive terminal. It always needs to travel there
What is electricity?
What are some of it’s traits.
The flow of electrons
Has amps and volts
What does this symbol mean V?
Voltage/Volts. The pressure of the electrons
What does this symbol mean I?
Amperes/Amps. How many electrons are flowing through the wire.
If you had two batteries with the same amount of electrons but one has less electrons being transmitted, what does that mean?
They have the same voltage (pressure) but the second has less Amperes (Less current)
You can change a water’s current by making the pipes bigger (More water can make it’s way to the other side) How do you do this with amps?
Resistance - measured in Ohms (r) or (Ω) Done by using different materials
What does higher Ohms do?
Higher resistance, it impedes the flow of electrons. (Like making a smaller pipe for less water to travel through)
REMEMBER OHMS IMPACTS AMPERES
What is a resistor?
Why do we need these?
Provides a circuit with ohms (resistance)
A lightbulb gets too much current to it and could cause it to burn out the lightbulb. Used so we don’t overload electronics.
what is a kohm?
what is a mohm?
Kila Ohm so 1000 ohms
mega ohm so 1,000,000
What do the colors mean on resistors?
1st number
2nd number
Multiplier - multiplies the number
Tolerance - how accurate is this resistor ± 2, means yeah, give or take 2%
if the first number is 2 and the second is 0 that comes to 20
What is an LED
Light-Emitting Diode
Have two leads
Longer - Anode+ (needs positive voltage source/terminal)
Shorter -o Cathode (needs negative voltage source/terminal)
If same length Cathode will have a small flat spot just above the lead
Tiny light bulbs
What is a diode
Must be hooked up in a circuit in a certain way.
How do you calculate resistance
Do it for an LED
Component - you need the resistance value for
Voltage of power source
subtract
Forward Voltage of component
divide
How many amps your component uses
LED - 9v battery - Manufacturer has forward voltage (3.2 in this case) - Manufacturer has this info (24MA) (This has to be converted to amps so multiply by .001)
resistance = (power source - Forward voltage / Amps)
resistance = ((9 - 3.2) / .024))
resistance - (5.8 / .024)
resistance = 240 ohms
How to connect LED to resistor to battery
On your 9v battery clasp the resistor to the cathode and press the end of it to the negative terminal.
Next take the Anode and press it against the positive terminal
viola
Explain a bread board
How would you connect the batter to the LED and a resistor?
Holes - for wires
Power Rails/busses - between red and blue lines, One long line from top to bottom are all connected, same for the second line. (So you could put positive on one for everything and negative on the other)
The middle - Every group of five holes are connected. The two seperated sections are
With two wires connected to the batters, plug the positive and negative terminals into their respective areas on the power rail/bus.
Insert the led annode into the positive rail/bus and the cathode into the middle of the board.
The resistor will have one wire in the middle with the LED and the other will go in a random set of five hole in the middle.
Use plug wire into the random resistor row then plug the other side into the negative power rail/bus
Ravine is the middle bit
What does a multi-meter do?
How would you test volts on a battery
How would you see the ohms your body emits compared to a battery?
Measures values of different things in a circuit like:
voltage
ohms
amps (pA)
Has two probes - test probes
Turn to volts (DC) red into positive, black into negative. It should say how much it has.
put fingers on probes on the ohms setting
Video 12
https://www.youtube.com/watch?v=XnJXySO94kU&list=PLah6faXAgguOeMUIxS22ZU4w5nDvCl5gs&index=12
