Education Technology

Light Intensity

Published on 08/27/2010

Activity Overview

Students investigate the relationship between light intensity and distance with a flashlight. They use the collected data to identify a mathematical model for the relationship. They then compare this model with the inverse-square law for an ideal point source.

Key Steps

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    Students investigate the relationship between light intensity and distance for a flashlight.

     

    First, students collect data on the intensity of light from a flashlight as a function of distance from the flashlight.

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    Students use regression tools to identify the functional form that best fits the data set. They examine the fit of the regression equation (a power equation) to the data, and discuss why a flashlight does not produce an inverse-square relationship of intensity to distance.