Equation 12 · Part 1 · Flight at the Energy Floor: Transport Selection to 2100
Symbol W_1
What this part means
is a part of this expression. Its role is fixed by the surrounding article and by the operations shown in the formula.
Its job in the formula
is a part of this expression. Its role is fixed by the surrounding article and by the operations shown in the formula.
Full expression→Symbol W_1→Article meaning
The passage around this formula
Jet fuel carries about 43 megajoules of chemical energy per kilogram, or roughly 11,944 watt-hours per kilogram [ 2 ] . A modern commercial lithium-ion cell, by contrast, runs 160 to 300 watt-hours per kilogram at the cell level, with specialty laboratory cells using silicon-anode and graphene-enhanced chemistries reaching a record of roughly 450 watt-hours per kilogram [ 3 ] — figures that describe a bare cell, not a certified aircraft pack, which must add cooling, structure, wiring, and safety margin on top. A widely cited 2018 estimate for a packaged aviation battery, including that overhead, put usable specific energy at around 160 watt-hours per kilogram, or about two percent of…
Learn the underlying idea
A subscript is a label attached below a symbol. It often selects a time step, component, category, or member of a sequence.
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Sources cited in the surrounding passage
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