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Light Intensity and Distance
Photosynthesis investigations often use a light source. The spreading out of light from a source obeys the inverse square law. The inverse square law links light intensity to distance from the light source.
Which of the following shows the inverse square law?
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Marking points
- 1 Selects the proportionality light intensity ∝ 1/distance².
Why this answer loses marks
I chose the formula with distance squared in the numerator.
Inverse-square means the squared distance acts reciprocally, so increasing distance reduces intensity.