Title: Facilitator Help Page: Lab 7-5 -- (Do Not Publish)
Course: Basic Electrical Theory and Wiring (Sandbox) > Section: Module 7: Ohm's Law

Answers and Tips

1. We want to drop 22V across the resistor with 2V for the LED. The current that we want is 0.02 A or 20 mA.  \(R\:=\frac{\:V}{I}\:=\frac{\:22}{0.02}\:=\:1100\:Ω\)
2. The student should use the 1K Ω or 1000 Ω resistor. They could use a combination which is acceptable to get a closer value to 1100 Ω, but it is not required.
3. The students should measure around 22V.
4. The student should measure around 2V.
5. The student should measure around 20 mA or 0.020 A.
6. The student should explain whether or not they think that Ohm's law worked. This should be more than just a yes or no.
7. Wiring:
  1. 24V+ should be brown wires.
  2. V- or Com should be blue wires.
  3. They should be using a breadboard.
  4. They should be using a push button that fits into the breadboard.
8. The rest of the questions are reminders for safety.

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