IN SERIES and PARALLEL CIRCUITS

1/31/96

equipment: single battery in battery pack

breadboard

multimeter

connecting wire

3 resistors (each with 15000 <= R >= 150 ); maximum R value

should be no more than 3x minimum R value

Prelab:

1) Measure and record the resistance values of the individual resistors. Either you or your partner should keep up with these resistors until the entire lab is complete.

Follow the procedure listed below for each of the 4 circuits you designed in part C of Lab D06 (except don't use your resistor values from D06).

2) Draw the circuit diagram (it should take up half a page); label the resistors R1, R2, R3 and the battery voltage, [[Delta]]Vb. Appropriately label all currents and voltage drops in the diagram.

3) By using (in no particular order):

the loop rule

the junction rule

the expressions for equivalent resistance discovered in lab D06

Ohm's law

properly relate all of the following. Then predict values for each of the following. Remember that numbers should not be in the first steps of your analysis; relationships should be well established before numbers come in. . Assume a battery voltage, [[Delta]]Vb , of 1.5volts. Organize your work clearly.

current through each resistor and through the battery

voltage change across each resistor

4) How should the power produced by the battery relate to the power dissipated in the individual resistors? Why?

Predict the power dissipated in each resistor and that supplied by the battery. Do your predicted values support your answers to the above? Show some work.

5) Organize your predicted values neatly in tabular form. You may want a separate table for each of the four circuits. In each table, leave space for additional columns for measured values, and percent differences.

In the lab:

1) Find a battery whose voltage is close to 1.5V. Measure and record the actual battery voltage, [[Delta]]Vb.

2) Build each of the circuits and measure the current through and the voltage drop across each resistor. Record these values in your data table(s).

4) Compare the predicted values to the directly measured values. Enter the results in the table(s).