0084.84 energy inputs for tilling a hectare of land
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本视频探讨了人类如何通过不同技术手段减少耕作所需的人力能量投入，并分析了从人力、畜力到拖拉机等不同耕作方式所需的总能量消耗及其变化趋势。
自动连播
0001.地球和太阳的尺度
0002.太阳系尺度
0003.离最近恒星距离的尺度
0004.银河系尺度
0005.星系间尺度
0006.星系的哈勃图像
0007.大爆炸介绍
0008.可观测宇宙半径
0009.可观测宇宙半径(更正)
0010.红移
0011.宇宙背景辐射1
0012.宇宙背景辐射2
0013.宇宙时间尺度1
0014.宇宙时间尺度2
0015.四种基本力
0016.恒星的形成
0017.变为红巨星
0018.白矮星和黑矮星
0019.小于可观测宇宙的宇宙
0020.星场和星云图片
0021.21 观星中的视差
0022.22 恒星视差
0023.23 通过视差求恒星距离
0024.24 恒星视差说明
0025.25 秒差距定义
0026.26 hubble's law
0027.27 lifecycle of massive stars
0028.28 supernova (supernovae)
0029.29 supernova clarification
0030.30 black holes
0031.31 cepheid variables 1
0032.32 why cepheids pulsate
0033.33 why gravity gets so strong near dense objects
0034.34 supermassive black holes
0035.35 quasars
0036.36 quasar correction
0037.37 galactic collisions
0038.38 earth formation
0039.39 beginnings of life
0040.40 ozone layer and eukaryotes show up in the proterozoic eon
0041.41 biodiversity flourishes in phanerozoic eon
0042.42 first living things on land clarification
0043.43 plate tectonics-- difference between crust and lithosphere
0044.44 structure of the earth
0045.45 plate tectonics -- evidence of plate movement
0046.46 plate tectonics -- geological features of divergent plate boundaries
0047.47 plate tectonics-- geological features of convergent plate boundaries
0048.48 plates moving due to convection in mantle
0049.49 hawaiian islands formation
0050.50 compositional and mechanical layers of the earth
0051.51 seismic waves
0052.52 why s-waves only travel in solids
0053.53 refraction of seismic waves
0054.54 the mohorovicic seismic discontinuity
0055.55 how we know about the earth's core
0056.56 pangaea
0057.57 scale of the large
0058.58 scale of the small
0059.59 detectable civilizations in our galaxy 1
0060.60 detectable civilizations in our galaxy 2
0061.61 detectable civilizations in our galaxy 3
0062.62 detectable civilizations in our galaxy 4
0063.63 detectable civilizations in our galaxy 5
0064.64 human evolution overview
0065.65 understanding calendar notation
0066.66 correction calendar notation
0067.67 development of agriculture and writing
0068.68 introduction to light
0069.69 seasons aren't dictated by closeness to sun
0070.70 how earth's tilt causes seasons
0071.71 milankovitch cycles precession and obliquity
0072.72 are southern hemisphere seasons more severe
0073.73 precession causing perihelion to happen later
0074.74 what causes precession and other orbital changes
0075.75 apsidal precession (perihelion precession) and milankovitch cycles
0076.76 firestick farming
0077.77 carbon 14 dating 1
0078.78 carbon 14 dating 2
0079.79 potassium-argon (k-ar) dating
0080.80 k-ar dating calculation
0081.81 chronometric revolution
0082.82 collective learning
0083.83 land productivity limiting human population
0084.84 energy inputs for tilling a hectare of land
0085.85 random predictions for 2060
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