为什么历史上的马德堡半球抽成真空后，两匹马也拉不开？
Why couldn't even teams of horses pull apart the Magdeburg hemispheres once evacuated?
半球内空气被抽走后内部接近真空，外界大气压从四面把两半紧紧压在一起。要拉开必须克服整个圆面积上大气压产生的总力，这个力极大，所以难以分开。
Once the air inside was pumped out, the near-vacuum left outside atmospheric pressure pressing the halves together from all sides. Pulling them apart means overcoming the huge total force of atmospheric pressure over the circular area, which is enormous.
难度 专业 · 适合 初中(12-15)
CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source
Paul Hewitt,《Conceptual Physics》Pearson 多版
Paul G. Hewitt, Conceptual Physics, Pearson, various editions
独立核验依据 · Independent verification: 核验依据 2 OPENLIBRARY 标识 /works/OL1930743W：Conceptual physics（按标题+
#大气压 #真空 #气压物理
为什么托里拆利实验里一根装满水银的玻璃管倒立后，水银柱会停在约76厘米高？
Why does the mercury column in a Torricelli experiment stop at about 76 cm when inverted?
管顶是真空，外界大气压从下方托住水银柱。当水银柱的重力与大气压产生的向上压力平衡时，液面就停在约760毫米处，这个高度正好量出了大气压的大小。
The top of the tube is a vacuum, and atmospheric pressure supports the mercury from below. The column stops when its weight balances the upward push of atmospheric pressure, at about 760 mm, which directly measures that pressure.
难度 专业 · 适合 高中(15-18)
CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source
Paul Hewitt,《Conceptual Physics》Pearson 多版
Paul G. Hewitt, Conceptual Physics, Pearson, various editions
独立核验依据 · Independent verification: 核验依据 2 OPENLIBRARY 标识 /works/OL1930743W：Conceptual physics（按标题+
#大气压 #液柱 #气压物理
为什么挤压钢笔的皮囊再松开，就能把墨水吸进去？
Why does squeezing and releasing a fountain pen's sac draw ink up into it?
挤压皮囊排出空气，松开后皮囊回弹使内部气压降低。外界大气压便把瓶中的墨水压进笔管，直到内外气压平衡，墨水就吸上来了。
Squeezing the sac expels air; releasing lets it spring back and lowers the internal pressure. Outside atmospheric pressure then pushes ink from the bottle up into the pen until pressures balance, drawing the ink in.
难度 进阶 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source
Paul Hewitt,《Conceptual Physics》Pearson 多版
Paul G. Hewitt, Conceptual Physics, Pearson, various editions
独立核验依据 · Independent verification: 核验依据 2 OPENLIBRARY 标识 /works/OL1930743W：Conceptual physics（按标题+
#气压 #压强差 #气压物理
为什么在山顶上烧水，往往不到100摄氏度就沸腾了？
Why does water boil below 100 degrees Celsius on a mountain top?
海拔越高，大气压越低，而液体的沸点随外界压强降低而下降。山顶气压低，水可能在八十多度就沸腾，所以食物更难煮透。
Higher altitude means lower atmospheric pressure, and a liquid's boiling point drops as outside pressure falls. On a peak the pressure is low, so water may boil in the eighties, making food harder to cook through.
难度 进阶 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source
Paul Hewitt,《Conceptual Physics》Pearson 多版
Paul G. Hewitt, Conceptual Physics, Pearson, various editions
独立核验依据 · Independent verification: 核验依据 2 OPENLIBRARY 标识 /works/OL1930743W：Conceptual physics（按标题+
#气压 #沸点 #气压物理
为什么吸盘挂钩压在光滑墙上就能挂住东西？
Why does a suction hook stay stuck to a smooth wall and hold things?
压吸盘时排出里面大部分空气，内部气压远小于外界大气压，外界大气压把它紧压在墙上。光滑表面防止漏气，挂重物时压力差提供摩擦力来承重。
Pressing the cup expels most of its air, so the inside pressure is far below atmospheric; the outside atmosphere presses it firmly against the wall. A smooth surface prevents leaks, and the pressure difference gives the friction needed to hold weight.
难度 进阶 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source
Paul Hewitt,《Conceptual Physics》Pearson 多版
Paul G. Hewitt, Conceptual Physics, Pearson, various editions
独立核验依据 · Independent verification: 核验依据 2 OPENLIBRARY 标识 /works/OL1930743W：Conceptual physics（按标题+
#气压 #吸附 #气压物理
为什么用吸管喝饮料时，纸杯不会被大气压压瘪？
Why isn't a paper cup crushed by atmospheric pressure when you drink through a straw?
杯内液面上方本来就是常压，吸气只降低吸管内的局部气压，杯身内外仍基本等压。而且纸杯有结构刚度，足以抵抗微小的压差，所以不会被压扁。
The air above the liquid in the cup is already at normal pressure; sucking only lowers the local pressure inside the straw, while the cup interior and exterior stay nearly equal. The cup's stiffness also resists small differences, so it is not crushed.
难度 入门 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source
Paul Hewitt,《Conceptual Physics》Pearson 多版
Paul G. Hewitt, Conceptual Physics, Pearson, various editions
独立核验依据 · Independent verification: 核验依据 2 OPENLIBRARY 标识 /works/OL1930743W：Conceptual physics（按标题+
#气压 #结构 #气压物理
为什么台风或龙卷风经过时，房屋的屋顶常被掀飞？
Why are roofs often blown off during a typhoon or tornado?
强风快速掠过屋顶，根据伯努利原理流速大处压强低，屋顶上方气压低于屋内。屋内较高的气压把屋顶向上顶出，于是被掀飞。
Fast winds sweep over the roof, and by Bernoulli's principle the high speed means lower pressure above it than inside the house. The higher indoor pressure pushes the roof upward, lifting it off.
难度 入门 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source
Paul Hewitt,《Conceptual Physics》Pearson 多版
Paul G. Hewitt, Conceptual Physics, Pearson, various editions
独立核验依据 · Independent verification: 核验依据 2 OPENLIBRARY 标识 /works/OL1930743W：Conceptual physics（按标题+
#伯努利 #气压 #气压物理