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  1. C

    What frequency value to use to find the correct time constant for a 22kΩ resistor?

    Hey guys, I have just been introduced to time constants and I'm having some trouble with this question. What frequency value do you plan to use to obtain the correct time constant for a 22 kΩ resistor? (Hint: It takes five time constants for a capacitor to go through the full charging...
  2. E

    Help on finding Thevenin Resistance and Current across resistor for RL Circuit?

    Hello! Good evening to you all! I'm currently brushing up on RC & RL circuits in preparation for an upcoming exam, and I found this circuit to be rather complex in its design. I've had a limited understanding of natural and step responses for RC & RL circuits, and this circuit certainly hits it...
  3. Matienzo

    Change value with linear pot

    Hi all The project I'm working on requires me to use two linear 20k potentiometers to change two values, time and temperature. What I'm doing is running a heating element for a certain period of time. The user selects the time(Range 5-9 min) and temperature (100-150C) and pushes a button, then...
  4. Matienzo

    Heated 35x50 mm surface.

    Hi there, I'm trying to create an electric heater for an insect repellent mat. The only constraint is that I must use a 18650 battery. The mats are about 35x50 mm and they need to be heated at about 130F. In the chat, Mike_2545 suggested a power resistor like this one and also pointed...

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