What is the capillary tube used for?
Capillary Tube – A tube with a calibrated inside diameter and length used to control the flow of refrigerant. It also connects the remote bulb to the thermostatic expansion valve, and/or the remote bulb to the thermostat.
What is the conical capillary tube?
A glass capillary tube is of the shape of truncated cone with an apex angle α so that its two ends have cross sections of different radii. If the surface tension of water is S, its density is ρ, and its contact angle with glass is θ, the value of h will be (g is the acceleration due to gravity)
How intermolecular forces affect capillary action?
Capillary Action. Intermolecular forces also cause a phenomenon called capillary action, which is the tendency of a polar liquid to rise against gravity into a small-diameter tube (a capillary), as shown in Figure 11.4. 3. When a glass capillary is is placed in liquid water, water rises up into the capillary.
What is a capillary tube?
Capillary tubing or capillary tubes are very thin tubes made of a rigid material, such as plastic or glass in which a liquid flows up into the tubes against gravity in a process called capillary action (capillarity). A fluid’s capillary action can occur in both vertical and horizontal directions.
How do capillary tubes collect blood?
Capillary blood is obtained by pricking a finger in adults and a heel in infants and small children. The specimen is then collected with a pipette, placed on a glass slide or a piece of filter paper, or is absorbed by the tip of a microsampling device.
What is in the capillary tube?
Capillary tubing or capillary tubes are very thin tubes made of a rigid material, such as plastic or glass in which a liquid flows up into the tubes against gravity in a process called capillary action (capillarity).
What is the shape when a non liquid is placed in a capillary tube?
For liquids which do not wet the solid have obtuse angle of contact, and liquid surface assumes a convex upward shape.
What is the relationship between strength of intermolecular forces and capillarity?
Capillarity is related to surface tension. If the attractive force between the glass walls of the tube and the substance are stronger than the intermolecular forces in the substance, than the edges of the liquid will be pulled above the surface of the liquid. This in turn helps pull the liquid up the tube.
What factors affect capillary action?
Capillary action occurs because water is sticky, thanks to the forces of cohesion (water molecules like to stay close together) and adhesion (water molecules are attracted and stick to other substances).
What happens when a capillary tube is placed in water?
Water rises inside the capillary tube due to adhesion between water molecules and the glass walls of the capillary tube. This adhesion, together with surface tension in the water, produces an effect called capillarity , with a characteristic concave surface.
How do you use a capillary tube?
Keep the finger in a downward position to maintain blood flow. Hold the Capillary Tube at an angle of 10 degrees below the collection site and touch the tapered end of the tube into the droplet of blood. Do not touch the skin with the tube.
How to adjust the height of a capillary tube?
Fix the capillary tube and the pointer in a cork, and clamp it in a rigid stand so that the capillary tubes and the pointer become vertical. Adjust the height of the vertical stand, so that the capillary tubes dip in the water in an open beaker.
How does capillary penetration occur in porous media?
Capillary penetration in porous media shares its dynamic mechanism with flow in hollow tubes, as both processes are resisted by viscous forces. Consequently, a common apparatus used to demonstrate the phenomenon is the capillary tube. When the lower end of a glass tube is placed in a liquid, such as water, a concave meniscus forms.
What are the phenomena and physics of capillary action?
Phenomena and physics of capillary action. Capillary penetration in porous media shares its dynamic mechanism with flow in hollow tubes, as both processes are resisted by viscous forces. Consequently, a common apparatus used to demonstrate the phenomenon is the capillary tube.