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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.
About the PNP Transistor
PNP (3906) Transistor: on when zero or no voltage to base pin Emitter: connected to positive battery source Base: o when zero or no voltage to base pin, when it is receiving voltage the pin is off Collector: connected to electronic component
How the final Project Warm circuit works
To have both sides of the bi-color LED light up we will need the PNP transistor in addition to the NPN transistor. The green light will turn on as the thermistor cools (green will represent cool) and the red light will turn on as the thermistor warms (red will represent warm). To make this happen we used a PNP transistor since it does the opposite of the NPN transistor. Both base pins of the transistors are connected to the same voltage level. When there is zero voltage applied to the PNP transistor it turns on and when there is zero voltage applied to the NPN transistor it off. When there is voltage applied to the PNP transistor it turns off and the NPN transistor turns on. In the circuit we built the green light is connected to the NPN transistor and the red light is connected to the PNP transistor, thus, when one is on the other will be off.
Why can't we see infrared?
our eyes were not created that way. God wanted us to be able to see what we need to survive and we can already see what we need. Bees andsnakes and other animals that can need to be able to see that to survive
Why does the red LED stay off?
The long pin of the red LED is receiving 4.5 volts and the short pin of the red LED is receiving 9 volts. Because of the difference in pressure the current wants to go counter clockwise, but the diode is preventing the current to go in that direction. The diode protects the LED from the reverse current flow.
Segmented LED Explained
i lernd that each sercit are difrint and that ther is a positive side and a negitiv side on a led light
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