How Entropy Powers The Earth (Big Picture Ep. 4/5)
This video is about how we don't just need energy to power our lives, we need *low entropy* energy! Thanks to Google Making and Science for supporting this series, and to Sean Carroll for collabora...
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The earth receives about 90 petajoules of energy from the sun every second.That’s a lot – enough to satisfy all human energy needs thousands of times over.However, the earth also radiates an equal amount of energy back into space as heat.(An almost equal amount, anyway -- the Earth is gradually heating up, but that's anotherstory.)So if energy in equals energy out, how can we possibly be using any energy to do anything?What matters, it turns out, isn’t simply energy – it’s useful energy.And energy is useful when it comes packaged in a low-entropy form.The total amount of energy in any closed system can’t change, of course -- energy is conserved.But that energy can be in different states of usefulness.There is useful energy in the water behind...
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The earth receives about 90 petajoules of energy from the sun every second.That’s a lot – enough to satisfy all human energy needs thousands of times over.However, the earth also radiates an equal amount of energy back into space as heat.(An almost equal amount, anyway -- the Earth is gradually heating up, but that's anotherstory.)So if energy in equals energy out, how can we possibly be using any energy to do anything?What matters, it turns out, isn’t simply energy – it’s useful energy.And energy is useful when it comes packaged in a low-entropy form.The total amount of energy in any closed system can’t change, of course -- energy is conserved.But that energy can be in different states of usefulness.There is useful energy in the water behind...
