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What EEME kids said they learned in Apr 2016

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How The Tunable Genius Light Works
The positive charge of the battery is connected to the emitter pin and then the photo sensor. The photo sensor acts as a resistor and as the photo sensor gets less light, it will increase in resistance. As the photo sensor receives less light it will decrease the voltage and current to the right pin of the photo sensor and PNP transistor. The right pin of the photo resistor is connected to the base pin of the PNP transistor. If the base pin of the PNP transistor does not receive voltage/current it will turn on, and will turn on the component. The second resistor connects the photo sensor and the POT. The middle pin of the POT is connected to the lower bottom bus and negative battery wire. The POT acts as a resistor, but can set a minimum and maximum resistance, allowing you to tune the circuit.
What is the bus part of the breadboard?
The breadboard is used to test circuits and connections between different wires and connectors. The top row of holes runs a connection all the way from the first hole to the hole all the way at the right end. However the positive row at the top does NOT connect to the negative row at the bottom. The same idea applies to the bottom row.
How does the bi-color LED circuit work
On the bi-color LED there are two LED lights inside. The long middle pin is the negative pin for both colors and each short pin must connect to the positive battery wire to light up each color of the bi-color LED. We actually made to separate circuits, on for each color of the LED. A bi-color LED is also known as a tri-state LED since it can light up 3 ways: red/red & green/green.
Multiple resistors like multiple dams
Resistors are like dams. When there are multiple next to each other, every time electricity flows through it gets reduced, every time it goes through a resistor.
Segmented LED Explained
the posetive prongs are all grouped togerther the negative prongs are alone
How does the addition of the NPN transistor work?
The IR LED is not bright enough to fully activate the IR phototransistor. Using the NPN transistor in our 2nd circuit gives more energy to the visible light LED allowing it to shine more brightly. The NPN transistor receives voltage from the IR phototransistor, which turns on the transistor.
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