Name: capillary action in narrow spaces
Uploaded: 2025-02-13T15:43:08.000Z
Duration: 1 min 19 s
Channel: JoVE

Capillarity refers to the movement of liquid in narrow spaces, driven by surface tension and adhesive forces between the liquid and nearby surfaces.
Such movement is commonly observed in thin tubes, porous materials, and other small spaces.
When a narrow tube, called a capillary tube, is placed into a liquid, the liquid level may rise or fall depending on the interaction of forces.
When the adhesive forces between the liquid and the tube are stronger than the cohesive forces within the liquid, the liquid rises, which is called capillary rise.
On the other hand, if the cohesive forces are stronger, the liquid falls, resulting in capillary depression.
Several factors that influence the height at which the liquid moves in a capillary tube are the contact angle between the tube and the liquid, the surface tension of the liquid, the liquid&#39;s density, the radius of the tube, and the effect of gravity.
Capillarity is important in both natural processes and technology, helping with water transport in plants, liquid absorption in porous materials, and technologies like microfluidic devices.

capillarity in fluid

Capillarity describes the movement of liquid in small spaces without external forces acting on it. The capillarity is driven by surface tension and adhesive interactions between the liquid and surrounding solid surfaces. This effect is often seen in narrow tubes, porous materials, and fine particles.
Surface tension is crucial to capillarity. It results from cohesive forces between liquid molecules at the liquid-air boundary, forming a skin that resists external forces. When the capillary tube is placed in a liquid, the liquid level changes based on the adhesive interactions between the liquid and the tube&#39;s surface. If these adhesive forces are greater than the liquid&#39;s cohesive forces, the liquid rises in the tube, known as capillary rise. If the cohesive forces are stronger, the liquid level drops, known as capillary depression.
The height to which the liquid rises or falls in a capillary tube is influenced by several factors, including the liquid&#39;s surface tension and density, the contact angle between the liquid and the tube, gravitational acceleration, and radius of the tube.
Capillarity is involved in many natural and industrial processes. It affects soil water and nutrient movement, which is essential for plant growth. In porous materials, it impacts liquid absorption and retention. Capillarity is also used in technologies like inkjet printing and microfluidics.

Capillarity in Fluid

Capillarity refers to the movement of liquid in narrow spaces, driven by surface tension and adhesive forces between the liquid and nearby surfaces.
Such ...

Education

JoVE Core

Civil Engineering

Unit 1

Fluid Properties

KEY TERMS AND CONCEPTS

capillary action in narrow spaces

Capillary action is the movement of liquid through narrow spaces without any outside force. It depends on surface tension and adhesion between the liquid and nearby solid surfaces. This effect is common in narrow tubes, porous materials, and fine particles.

Surface tension comes from cohesive forces between liquid molecules at the liquid-air boundary. These forces create a thin skin that resists outside pressure. When a capillary tube is placed in a liquid, the liquid level changes because of its interaction with the tube surface.

If adhesion is stronger than cohesion, the liquid rises in the tube. This is called capillary rise. If cohesion is stronger, the liquid level drops. This is called capillary depression.

The amount a liquid rises or falls depends on several factors. These include surface tension, liquid density, the contact angle with the tube, gravitational acceleration, and the tube radius. Capillarity matters in nature and in technology. It helps move water and nutrients in soil for plant growth, affects liquid absorption and retention in porous materials, and is used in inkjet printing and microfluidics.

Capillary Action in Narrow Spaces

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Capillary action is the movement of liquid through narrow spaces without any outside force. It depends on surface tension and adhesion between the liquid and nearby solid surfaces. This effect is common in narrow tubes, porous materials, and fine particles. Surface tension comes from cohesive forces between liquid molecules at the liquid-air boundary. These forces create a thin skin that resists outside pressure. When a capillary tube is placed in a liquid, the liquid level changes because of...

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key terms and concepts

Learn how capillary action moves liquid through narrow spaces using surface tension and adhesion, and see its role in plants, porous materials, and printing.

Capillary Action in Narrow Spaces | JoVE K12

JoVE Core Civil Engineering offers a foundational exploration of essential construction materials such as bricks, stones, steel, wood, and concrete, along with fluid mechanics topics like flow over immersed bodies, open channel flow, and dimensional modeling. It also covers key surveying concepts, including leveling, traverse adjustments, curve design, topographic mapping, and geospatial technologies (GPS & GIS). Science-in-action videos showcase laboratory research on materials, fluids, and surveying practices in real-world engineering systems.

civil engineering

Capillary Action in Narrow Spaces

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