Can You Resist This?
Students explore Ohm's lawCopyright 2004 Microsoft Corporation, One Microsoft Way, Redmond, WA 98052-6399 USA. All rights reserved.
This lab demonstrates Ohm's law as students set up simple circuits each composed of a battery, lamp and resistor. Students calculate the current flowing through the circuits they create by solving linear equations. After solving for the current, I, for each set resistance value, students plot the three points on a Cartesian plane and note the line that is formed. They also see the direct correlation between the amount of current flowing through the lamp and its brightness.
The concept of Ohm's law is the basis for explaining the relationship between resistance, current, and voltage. Electrical engineers use the equation everyday in the analysis of electrical circuits. Engineers have developed programs to do the work of predicting and optimizing the efficiency of the circuits. All electronic devices are composed of circuits, which engineers must design or debug making it essential to understand Ohm's Law. Students are asked to think about this in the post-activity assessment.
After this activity, students should be able to:
- State Ohm's law V=IR and explain the relationship between resistance, voltage and electric current.
- Calculate the electric current flowing through a circuit.
- Set-up a circuit using the correct circuit components and a breadboard.