1. Light at a Distance Jessica, Charlie, Courtney, and Ashley

2. Set-Up To perform this lab we had a dark room, a light bulb, table, tape measurer, and a light sensor. The light bulb remained at the same position throughout the lab, while the light sensor changed its distance from the light bulb and then collected the intensity of the light.The actual brightness of the bulb remained the same but the perceived brightness of the bulb changed with the distance.

3. Objective 1) Pick data points & collect the light bulbs intensity at each point 2) Plot data on a graph to find out type of regression 3) Use a calculator to perform regression and write equation 4) Analyze the regression to find the correlation between distance from the light bulb and intensity of light 5) Repeat these steps using the Inverse Square Relationship Y= A X2X2

4. Independent Variable (Controlled): distance (cm) from the light bulb Dependent Variable: intensity of the light

5. Data As the distance from the light bulb increases, the intensity decreases.

6. Graph

7. Equations y=-0.58x+0.57 This number describes the rate of change of intensity in respect to distance. This number represents the intensity of the light bulb. X is the distance from the light bulb. Linear Regression Equation:

8. Equations Exponential Regression Equation: y=1.22(0.99)^x This number, the base, represents the rate at which the percent of initial intensity changes in respect to X. This number represents the initial intensity of the light. X is the distance from the light bulb.

9. What did we learn from this activity? The appearance of how bright the light is depends on how far away you are standing from the light bulb. The actual brightness of the light remains constant even though our eyes perceive the brightness to be changing (meaning the appeared intensity decreases as you move further from the light).