Bradshaw,+J.

Problem Statement:how can the strenth of light be measured ?

Hypothesis: I am going to prove that the lumen is the most acurate way to measure light.

Background Information : light is a form of energy. light travels in forms of waves. light can pass through any object or space. This is why we see the light of the sun and stars.

Controlled variables : The lightbulb, the lamp, the flashlight, the distance and the photometer all stayed the same over the course of the experiment.

Independant Variables: The light units, the the candela, the luminance and lumen changed tough out the experiment.

Dependant Variables : The light measurement results changed between the units of the light.

Reasearch : light can travel acuratley at 186,920m per second. When exposed to a shiny surface the light can change direction. Non- shiny objects can be reflected. Reflective material used on clothes make visible to other lights. Light travels at different speeds in different material. Light Waves behave the same way. lights bend well in plastic, glass, and water. The exact speed of light can not be measured with total accuracy. The candela is a unit of luminous intensity. one candela is defined as the luminous intensity 1/600,000 square meter of a projected light. A unit flow or luminous flux is a lumen. The lumen rating of a lamp is a mesure of the total light output. The lumen is the most common measurement of a light output. Luminance is the quality of the quantity of light that is measured in lumens.