Answers and Tips
- 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.
- 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.
- The students should measure around 22V.
- The student should measure around 2V.
- The student should measure around 20 mA or 0.020 A.
- The student should explain whether or not they think that Ohm's law worked. This should be more than just a yes or no.
- Wiring:
- 24V+ should be brown wires.
- V- or Com should be blue wires.
- They should be using a breadboard.
- They should be using a push button that fits into the breadboard.
- The rest of the questions are reminders for safety.

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