light bulbs, ideas, inspiration @ Pixabay

One of the most common questions people ask is “How far away is the light?” This question can be answered by understanding the inverse square law. As it turns out, as you get farther from a point source of illumination (light bulb), the intensity diminishes in proportion to 1/d2. That means that for every time someone moves twice as far away from a light bulb, they will experience four times less light energy than when they were closer to it. – When someone is three meters away from the light bulb, they will experience one fourth of its intensity. – The human eye cannot detect a difference in brightness between two different intensities unless there is an order of magnitude (ten times) difference in these quantities. We are able to see this because our eyes have receptors which can distinguish small differences in illumination levels even if their absolute values differ by less than 0.01%. Summary: This blog post describes how distance affects the amount of light energy that reaches us at a specific location and time (intensity). It also discusses what we need for observing changes in lighting intensities and how observation makes it possible for us to understand more about physics as well as our environment around us!


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