为什么水流顺着汤勺的背面流，而不是笔直落下？
Why does a stream of water follow the back of a spoon instead of falling straight down?
当水流贴近弯曲表面且速度够快时，内侧低压与表面吸附把它吸住沿曲面流动，这叫康达效应。直到曲面结束或速度不足，水流才脱离表面。
When a stream runs close to a curved surface fast enough, low pressure on the inner side and surface adhesion make it cling and follow the curve, called the Coanda effect. The flow only leaves when the surface ends or the speed drops.
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
Serway & Jewett,《Physics for Scientists and Engineers》第9版,Cengage Learning,2013
R. A. Serway and J. W. Jewett, Physics for Scientists and Engineers, 9th ed., Cengage Learning, 2013
独立核验依据 · Independent verification: 核验依据 2 ISBN 978-1-337-55327-8
#附壁 #流体 #流体物理
为什么钢铁造的大船比水重很多，却能浮在水面上？
Why can a steel ship, far heavier than water, still float?
物体浮力等于它排开的水的重量。船体做成空心，整体平均密度小于水，排开的水量足以产生等于船重的浮力，于是漂浮。关键在于排开的水而非材料本身。
Buoyancy equals the weight of the displaced water. A hollow hull gives the ship an average density less than water, and the volume it displaces produces a buoyant force equal to its weight, so it floats. What matters is displaced water, not the material alone.
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
Serway & Jewett,《Physics for Scientists and Engineers》第9版,Cengage Learning,2013
R. A. Serway and J. W. Jewett, Physics for Scientists and Engineers, 9th ed., Cengage Learning, 2013
独立核验依据 · Independent verification: 核验依据 2 ISBN 978-1-337-55327-8
#浮力 #阿基米德 #流体物理
为什么把装满水的瓶子倒过来，水不会一下子全流光，而是咕噜咕噜地漏？
Why doesn't water pour out all at once when you invert a full bottle, but glugs out instead?
瓶子口小，水流出时内部需要进气来补位，否则内部气压降低会拖慢水流。空气只能间歇性挤进去，于是水一阵阵地咕噜流出，整体变慢。
With a small mouth, water leaving must be replaced by incoming air, or the internal pressure would drop and slow the flow. Air can only squeeze in intermittently, so the water glugs out in pulses and overall runs slowly.
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
Serway & Jewett,《Physics for Scientists and Engineers》第9版,Cengage Learning,2013
R. A. Serway and J. W. Jewett, Physics for Scientists and Engineers, 9th ed., Cengage Learning, 2013
独立核验依据 · Independent verification: 核验依据 2 ISBN 978-1-337-55327-8
#气压 #流率 #流体物理
为什么飞机那么重，却能在空中飞行不掉落？
Why can such a heavy airplane stay up in the air instead of falling?
机翼上表面弯曲、下表面较平，气流过翼时上表面流速快、压强低，下表面压强高，形成向上的升力。当升力等于飞机重力，飞机就能起飞和巡航。
A wing's curved upper surface and flatter lower surface make air move faster on top at lower pressure while the bottom stays at higher pressure, creating upward lift. When lift equals the plane's weight, it can take off and cruise.
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
Serway & Jewett,《Physics for Scientists and Engineers》第9版,Cengage Learning,2013
R. A. Serway and J. W. Jewett, Physics for Scientists and Engineers, 9th ed., Cengage Learning, 2013
独立核验依据 · Independent verification: 核验依据 2 ISBN 978-1-337-55327-8
#升力 #伯努利 #流体物理
为什么倒啤酒时如果太急，杯子里会冒出大量泡沫溢出？
Why does pouring beer too fast fill the glass with foam that overflows?
快速倒酒让大量二氧化碳突然释放，并卷入空气，形成许多小气泡。泡沫比液体体积大得多，若杯壁不光滑或角度不当，泡沫迅速堆积就溢出来。
Pouring fast suddenly releases lots of dissolved carbon dioxide and traps air, forming many small bubbles. Foam occupies far more volume than liquid, and with a rough wall or wrong angle it builds up and overflows.
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
Serway & Jewett,《Physics for Scientists and Engineers》第9版,Cengage Learning,2013
R. A. Serway and J. W. Jewett, Physics for Scientists and Engineers, 9th ed., Cengage Learning, 2013
独立核验依据 · Independent verification: 核验依据 2 ISBN 978-1-337-55327-8
#气泡 #表面张力 #流体物理
为什么两艘船并排快速行驶时会彼此靠拢，甚至有危险？
Why do two ships sailing side by side at speed drift toward each other, sometimes dangerously?
两船之间的水流被挤窄、流速加快，根据伯努利原理压强降低，而船外侧水压相对较高，就把两船推向中间。这就是流体中的相吸现象。
The water between the ships is squeezed into a narrower channel and flows faster, so by Bernoulli's principle its pressure drops while the outer pressure stays higher, pushing the ships together. It is a fluid attraction effect.
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
Serway & Jewett,《Physics for Scientists and Engineers》第9版,Cengage Learning,2013
R. A. Serway and J. W. Jewett, Physics for Scientists and Engineers, 9th ed., Cengage Learning, 2013
独立核验依据 · Independent verification: 核验依据 2 ISBN 978-1-337-55327-8
#伯努利 #压强 #流体物理
为什么按压式喷雾器一抽气就能把液体变成雾喷出来？
Why does a pump sprayer turn liquid into a mist when you squeeze it?
喷口处高速气流使附近压强降低，容器内液体在大气压作用下沿细管被压上来，到出口被气流撕成细小液滴形成雾。这是文丘里效应与伯努利的结合。
The fast airstream at the nozzle lowers the local pressure, and atmospheric pressure pushes liquid up a thin tube; at the exit the airstream shreds it into fine droplets, forming a mist. It combines the Venturi and Bernoulli effects.
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
Serway & Jewett,《Physics for Scientists and Engineers》第9版,Cengage Learning,2013
R. A. Serway and J. W. Jewett, Physics for Scientists and Engineers, 9th ed., Cengage Learning, 2013
独立核验依据 · Independent verification: 核验依据 2 ISBN 978-1-337-55327-8
#文丘里 #雾化 #流体物理
为什么向两张平行悬挂的纸中间吹气，纸反而贴到一起？
Why do two hanging sheets of paper move toward each other when you blow between them?
中间气流速度快、压强低，而纸外侧是静止的正常大气压。外侧较高压力把两张纸推向中间低压区，于是它们贴拢。这也是伯努利效应的体现。
The air between the sheets moves fast and its pressure drops, while the outside is at normal atmospheric pressure. The higher outside pressure pushes the sheets inward toward the low-pressure zone, bringing them together, another Bernoulli effect.
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
Serway & Jewett,《Physics for Scientists and Engineers》第9版,Cengage Learning,2013
R. A. Serway and J. W. Jewett, Physics for Scientists and Engineers, 9th ed., Cengage Learning, 2013
独立核验依据 · Independent verification: 核验依据 2 ISBN 978-1-337-55327-8
#伯努利 #压强 #流体物理
为什么用吸管吸饮料，液体就会顺着管子升到嘴里？
Why does liquid rise up a straw into your mouth when you suck on it?
吸气时吸管内的空气被抽走，管内气压低于外界大气压，外界大气压便把杯中的液体压进吸管并送入口中。本质上是大气压在推而不是嘴在拉。
Sucking removes air from the straw, lowering its internal pressure below atmospheric; the outside atmospheric pressure then pushes the liquid up the straw into your mouth. It is really atmospheric pressure pushing, not your mouth pulling.
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
Serway & Jewett,《Physics for Scientists and Engineers》第9版,Cengage Learning,2013
R. A. Serway and J. W. Jewett, Physics for Scientists and Engineers, 9th ed., Cengage Learning, 2013
独立核验依据 · Independent verification: 核验依据 2 ISBN 978-1-337-55327-8
#气压 #压强差 #流体物理
为什么洗澡时开着热水，浴帘会往浴缸里面飘？
Why does the shower curtain billow inward toward the tub when you run hot water?
水流和暖湿空气在帘内形成向下流动，局部流速大、压强略低于帘外静止的空气。外侧较高气压把浴帘推到里面，类似伯努利与烟囱效应的结合。
The falling water and warm humid air create a downdraft inside, where the faster flow lowers the pressure slightly below the still air outside. The higher outside pressure pushes the curtain inward, a mix of Bernoulli and chimney effects.
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
Serway & Jewett,《Physics for Scientists and Engineers》第9版,Cengage Learning,2013
R. A. Serway and J. W. Jewett, Physics for Scientists and Engineers, 9th ed., Cengage Learning, 2013
独立核验依据 · Independent verification: 核验依据 2 ISBN 978-1-337-55327-8
#伯努利 #气流 #流体物理