Which color of light shines brightest through fog? Fog scatters some wavelengths of light more than others. You can test this with a simple jar of cloudy water.
Fill a jar with water and stir in two teaspoons of milk. This creates a foggy liquid that scatters light. Place a light meter behind the jar and a flashlight in front. Cover the flashlight with different colors of cellophane and record the brightness each time.
Yellow light measured 8.8 lumens, the highest reading. Orange came close at 8.4. Blue scored lowest at 6.3. Longer-wavelength colors pass through the cloudy liquid with less scattering.
Hypothesis
The hypothesis is that yellow light will shine the brightest through the liquid because yellow light has the longest wavelength.
Fog scatters some wavelengths of light more than others, letting longer waves pass through more easily. Yellow light measured 8.8 lumens through a jar of cloudy water, the highest reading. Blue scored lowest at 6.3, because its shorter wavelength scatters more on the way through.
Some wavelengths pass through a foggy liquid with less scattering than others. Fill a jar with water, stir in two teaspoons of milk, and shine a flashlight through it covered with different colors of cellophane. A light meter behind the jar records the brightness each time. Yellow light measured 8.8 lumens, the highest reading. Orange came close at 8.4. Blue scored lowest at 6.3. Longer-wavelength colors pass through with less scattering.
Method & Materials
You will need to buy colored cellophane wrap and rent or buy a light meter. Then, get a jar and remove the label. Cut different colors of cellophane wrap and fold them into squares. Fill the jar with water and add two teaspoons of milk to the water. Stir milk and water to form a cloudy liquid. Put the light meter behind the jar and the flashlight in front of the jar. Shine the flashlight through the cloudy liquid into the light meter. Put different colors of cellophane wrap film over the flashlight to make different colors of light.
You will need a jar with no label, milk, water, a flashlight, cellophane wrap colored film, and a light meter.
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