Equivalent Resistance

Equivalent Resistance

Author: Ryan Melvin
  • Students will be able to differentiate series and parallel circuits.
  • Students will be able to calculate equivalent resistance of series, parallel and combination circuits.


Series Circuit


•Same current through both bulbs.
•If a bulb is removed, all current stops.
•Equivalent resistance increases
Parallel Circuit
•Same voltage drop across each bulb
•If one bulb is removed, current still flows (houses)
•Equivalent resistance decreases 


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Series and Parallel Circuits

This video details the differences between series and parallel circuits. It is meant to be viewed after an in-class exploratory component where students attempt to create a variety of functioning circuits.

7.4 Equivalent Resistance

Equivalent Resistance Worksheet

Problems about series and parallel circuits

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