空间站里的水为什么能飘成一团球，而不像在地上摊成一摊？
Why does water float as a ball in the space station instead of spreading into a puddle?
在失重环境里没有“往下流”的重力，水靠表面张力把自己缩成表面积最小的球形。地面上重力盖过了表面张力，水才会摊开。
In weightlessness there's no gravity pulling water down, so surface tension shapes it into the smallest-area form: a sphere. On Earth gravity overwhelms surface tension and the water spreads out.
难度 进阶 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-10-03 · 4 条独立证据
来源 · Source
Halliday, Resnick, Walker,《Fundamentals of Physics》第10版,Wiley,2013
David Halliday, Robert Resnick, Jearl Walker, Fundamentals of Physics, 10th ed., Wiley, 2013
独立核验依据 · Independent verification: 核验依据 3 angusrobertson.com.au
#失重 #表面张力 #水球
在太空里火焰没有“往上”的对流，为什么烧得更慢、更省？
With no upward convection in space, why does a flame burn slower and leaner?
地面上热烟气往上飘，不断把新鲜氧气拉来、把废气带走，火烧得旺。太空里没有这股“抽风”，氧气只能靠慢慢扩散过来，所以火焰更小、更圆、更省燃料。
On Earth hot gas rises, continuously pulling in fresh oxygen and carrying away waste, so fire burns vigorously. In space nothing 'drafts' the flame; oxygen must diffuse in slowly, so it's smaller, rounder and uses less fuel.
难度 进阶 · 适合 初中(12-15)
CC BY 4.0 · 已核验 · Verified 2026-10-03 · 4 条独立证据
来源 · Source
Halliday, Resnick, Walker,《Fundamentals of Physics》第10版,Wiley,2013
David Halliday, Robert Resnick, Jearl Walker, Fundamentals of Physics, 10th ed., Wiley, 2013
独立核验依据 · Independent verification: 核验依据 3 angusrobertson.com.au
#失重 #火焰 #扩散