Posts Tagged ‘ohm’s law’

Resistance in series and parallel

Friday, May 6th, 2011

Useful resources for reviewing resistance:

Resistance and Ohm’s Law

Resistance

Calculating resistance in series and parallel

Useful site showing calculations for resistors in series and parallel.  And another one.

Ohm’s Law

Friday, April 29th, 2011

We are going to investigate the relationship between voltage, current and resistance in an electrical circuit.  This is called Ohm’s Law.   This might be useful to read first.

Log on to the online circuit construction kit we have been using in class.  Build a circuit containing 1 battery and 1 resistor in series.  Add in an ammeter and a voltmeter.  REMEMBER – ammeters in series and voltmeters in parallel.  Record the values for current, voltage and resistance in this table. Ohm’s Law data

Now change the resistance.  Record the data for current and voltage in your table.  Collect at least 10 pieces of data – or more if you need to, until you see a pattern emerging.  Add in another battery, and take some more readings.  Keep adding in batteries and recording data.  Can you come up with a relationship between each of these three quantities?

Using excel, draw a graph of voltage against current.  Add a trendline, label axes, give a title.  What does the gradient of the line tell us?

Hand in your data tables and graph for grading.  FINALRubric DCP