Resistors in Series and Parallel E-practical
Introduction
Resistors impede the flow of current in a circuit. We use them in electrical and electronic circuits to control the flow of current. The higher the resistance the less current that flows. However, there are two different ways we can connect resistors together, either in series or in parallel. This experiment will allow you to investigate the combined resistance of resistors connected both ways.
Realistic experimental technique
E-practicals are 3d, highly realistic emulations based on a blend of theory and the actual practicals, giving an authentic experience of doing the actual practical in a laboratory. Students operate the apparatus, make measurements and obtain their own results. It is designed to reproduce the experience of performing the practical rather than simply demonstrating the underlying physics. Like a real experiment, it can be done badly. Careless setup or measurements can produce poor results, so students have to apply experimental technique and take care with their measurements.
Useful when laboratory access is limited
Ideal for preparation before a practical, revision afterwards, missed practicals, home study, or demonstrating an experiment when setting up the real apparatus isn't practical.
Works directly in a browser
No installation is required. Windows, Mac and suitable mobile devices can run the WebGL e-practical.
See it in Action
This shows how the e-practical can be used. In particular it shows how the student or teacher interacts with the apparatus and how the interaction can be controlled using the mouse or the alternative on-screen controls.
What students do
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Click on a resistor and then click on the breadboard for where you want the resistor to be placed.
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You can return a resistor to the cork mat by clicking on it while it is positioned on the breadboard. The multi-meter will read the current for the circuit whatever the configuration.
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Using only the 33 Ohm resistors place one on row 1 where the yellow strip is.
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Record the current and calculate the resistance of the resistor using the assumed voltage of the battery and the current reading.
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Return the resistor to the cork mat.
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Now place two of the 33 Ohm resistors in series on row 3 of the breadboard,
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record the current and calculate the combined resistance from it.
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Return the two resistors to the cork mat.
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Now place three of the 33 Ohm resistors onto row 5 of the breadboard.
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Again, calculate their combined resistance from the recorded current.
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Repeat the above for different values of resistor.
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Repeat using the gaps in rows 7, 9 and 11 for resistors in parallel.
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For resistors connected in series, you should be able to verify that the total resistance in each case is the sum of the individual resistances.
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For resistors connected in parallel, you need to confirm the more complicated formula.
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1/R = 1/R1 + 1/R2 +…
What you get
The application is supplied as a PowerPoint which provides background, a synopsis of what the student will learn, a description of the Physics involved, a description of the apparatus, the independent and dependent variables, the method, a link to the interactive online e-practical, analysis of the results and further discussion.
E-practical
Runs in a modern web browser. No software installation required. Recommended or desktops but will run successfully on tablets of medium to large size with a browser that supports WebGL.
School/Department licence £9.99
Valid for 1 year