Phy222: Lab Activitycircuit Design Lab Score: ______

Phy222: Lab ActivityCircuit Design Lab Score: ______

Names: ______

Circuit Design Lab

In this lab activity you will design your own circuits to demonstrate some of the principles of series and parallel circuits that we covered in class.

Preparation for this lab (design phase):

• Design Circuits & Experiments that will prove the circuit principles listed below. It’s possible to design a circuit/experiment that demonstrates several principles at once. Feel free to do so.
  We will set aside some equipment in the physics lab. Please feel free to stop by and try it out.

• Hand in your designs & procedures at the beginning of the lab (make a photocopy).

Lab part:

• Set up the circuits, take and record the measurements needed to support the principle.

Lab Report

Part 1: Circuit Designs

Turn in your hand-drawn but legible and clear designs at the beginning of this week’s lab. An example of what to do is posted on the website.

Part 2: Circuit Designs, Procedures, Data, Analysis

In your write-up you will show your circuits, describe your procedure and summarize how your excellent data proves you correct. Please word-process all text integrating your circuit diagrams throughout. Your diagrams should not appear at the end of your report but rather be included in the report where you present the data and your discussion. The due date for the report will be Thursday, the week after the lab.

Tasks to Accomplish

Design circuits that demonstrate all of the principles listed below. Set up the circuits and take measurements to show that the principle in question is indeed correct.

Principles of Series Circuits

1. The voltages across each circuit element add to that of the battery.
2. The current through each circuit element is the same.
3. Higher resistances have higher voltage across them.
4. Resistors added in series to any circuit increase the resistance to current in the circuit.

Principles of Parallel Circuits

1. Voltages across each circuit element are the same.
2. The current through each parallel circuit element adds to that going through the battery.
3. The higher resistance in a parallel circuit has less current.
4. Resistors added in parallel to any circuit reduce the resistance to current in the circuit.

General Principles

1. A branch in a circuit that contains a short has no voltage across it.
2. A branch in a circuit that is open has all the voltage across it.
3. A battery is a constant voltage source.
4. A battery is not a constant current source.
5. Ammeters have very little internal resistance.
6. Voltmeters have very large internal resistance.