Introduction

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You may have noticed that a light source appears to be brighter when you are close to it and dimmer when you are farther away. This is because the amount of the light that enters your eye increases as you move closer to the light source.

There are several ways to measure the brightness of light. In this experiment, you will use a Light Sensor to measure the illumination detected by the sensor in lux. You will observe how illumination varies with distance and compare the results to a mathematical model.

Objectives

Determine the mathematical relationship between illumination and distance from a light source.