Fluid Friction: Explanation, Factors Affecting, and Examples

Fluid friction refers to the force that resists the movement of liquid within itself or in another medium.

• The molecules in liquid move constantly due to less attractive forces between them.
• Due to this movement, the conflict occurs within the fluid and with the external medium as well.
• So, internal friction occurs all along the layers of liquid that are relative to each other.
• The fluid Friction depends on the thickness of the fluid.
• Viscosity infers the internal resistance to flow, lesser the viscosity of the fluid, the greater the frictional force.
• It is usually used in the water slides allowing the people to slide down gently.

Key Terms: Viscosity, Fluids, Fluid friction, Dry friction, Water, Air, Solid, Force, Lubricants, Resistance, Internal resistance, Atoms, Interatomic force

---

Types of Friction

[Click Here for Sample Questions]

Different types of friction are as follows

• Dry Friction: It refers to the resistance to relative lateral motion produced between two solid surfaces. 
• Fluid Friction: It refers to the friction produced between the thick fluid layers moving parallel to each other.  
• Lubrication Friction: It refers to the fluid friction where the surfaces of two solids are lubricated with the materials to make the surface smooth.
• Skin Friction: It refers to the force that resists the motion of a fluid throughout the body surface.
• Internal Friction: It refers to the force between the particles of a solid surface that resists their motion while it deforms.

---

What is Fluid Friction?

[Click Here for Sample Questions]

The internal resistance that arises when fluid layers move relative to one another is known as fluid friction.

• This internal resistance is known as viscosity.
• Any material that can flow is known as fluid.
• Therefore water and air are both considered as fluid.
• Air resistance is caused by fluid friction between air and a surface.
• When an object moves through the air, it pushes the air out of the path and the air pushes back.
• This push of air on the moving object causes friction, which slows it down.

• As a result, moving vehicles such as cars, buses, aircraft, and rockets experience frictional forces.

Also check: 

---

Factors Affecting Fluid Friction

[Click Here for Sample Questions]

Usually, friction occurs in liquids. So it is called the fluid Friction. The factors on which the fluid Friction depends and is affected are as follows:

Speed of Object

The friction increases with the speed of the Object.

• The higher the speed of the Object, the greater the fluid Friction.
• The lesser the speed of the Object, the lesser the fluid Friction.

Shape of Object

An object with a streamlined shape experiences less friction. While the non-streamlined objects have more fluid Friction.

Size of Object

The larger object faces more friction. The small object faces less friction. It is due to the surface area of the object.

Nature of Fluid

The fluids with more thickness and viscosity face more friction. It is due to the close arrangement of molecules, greater friction occurs.

Viscosity of Fluid

The more is the density of the fluid, the more viscosity, and more friction. Due to the density, molecules inside are restricted from motion, and hence the resistance is increased.

Temperature of Fluid

The fluid friction is directly proportional to the temperature. The fluid friction increases along with the increase in temperature.

---

Examples of Fluid Friction

[Click Here for Sample Questions]

The following are examples of fluid friction

Shaving cream

When we apply shaving cream on the face, a foamy layer is formed. This causes friction between the face and cream reducing harm to the skin.

The flow of ink in a pen

The ink is packed in the refills for all pens.

• It doesn’t flow and doesn’t get leaked.
• It is due to the internal friction that the fluid remains without flowing.

Cleaning on a wet place

We always clean a place by pouring some water on the area. This makes our job easier with less amount of water.

Air pushing against the hand

The air flows so fast that we cannot stand it at times. When we place our hand firmly against it, friction between hand and air occurs.

Moving of submarine into the water

The submarine is a heavy body that runs with the fuel inside the water. Due to its heavy weight and contact with water, there is friction occurring.

Also check: 

---

Things to Remember

• Fluids are non-fixed-shape substances that flow easily due to larger intermolecular spaces.
• Friction is the force that resists the relative motion between two bodies in contact.
• Fluid Friction is the force that opposes the motion of molecules within the fluid and the external medium it is in contact with.
• The fluid friction depends on the shape, size, speed, and nature of fluid or objects.
• The two conditions where fluid friction occurs are due to the internal movement of molecules and the interaction of the fluid with the external medium.
• There are five types of friction which include fluid friction, skin friction, lubricant friction, dry friction, and internal friction.