Series & parallel circuits

background [prelab assignment (20 points) due at the begining of lab]

1. sketch 2 circuit diagrams showing a battery connecting (i) 2 resistors in series and (ii) 2 resistors in parallel with each other; include ammeter(s) to illustrate Kirchoff's current law at a junction / node and the placement of a voltmeter(s) to measure the voltage across each resistor in the circuit.

2. calculate expected voltage across each resistor and current thru each resistor in the above circuit diagram using a 1.5 battery, 10 kΩ, and 5.1 kΩ resistors.

purpose

1. connect battery to a pair different resistors in series versus parallel. measure / record ___; include circuit diagram, where label (i) resistors as R1 and R2, (ii) ammeters, and (iii) voltmeter, which corresponds to a subsequent table with measurement (of current, voltage, or resistance) and calculation of expected value based on measurment of battery voltage and resistance of each resistor.

a. voltage across each resistor in the circuit and the battery

b. current into / out of each resistor

show calculations to support / refute Kirchoff's voltage / current laws based on preceding observations / measurements

materials

batteries, resistors (10 kΩ ; 5.1 kΩ ), 7 different color wires + alligator clips

multimeter & 3 ammeters / groups

methods / data analysis

student design

content of lab report [25 points]

introduction: (i) sketch (i.e. no free-hand sketches; use below resource) appropriate circuit diagrams, (ii) calculations for expected current thru each resistor in the circuit and the voltage across each resistor, and (iii) table summarizing your calculations.

results: data table of your measurments corresponding to the preceding circuit diagrams

discussion: support / refute Kirchoff's voltage / current laws based on preceding observations / measurements / calculations.

resources

example of series / parallel circuit lab handout

free circuit drawing tool