friction is affected by the nature of the surfaces in this way that ..... if the surface will be rough then friction will be more and if the surface will be flat and plain , smooth or oily then there will be less friction.

Friction and the Nature of the Surface

Friction is a force that opposes the relative motion or tendency of motion between two surfaces in contact. The nature of the surface plays a significant role in determining the magnitude of friction between two objects.

Types of Friction
Friction can be categorized into three types: static friction, sliding friction, and rolling friction. Static friction is the force that prevents two surfaces from sliding past each other when they are at rest. Sliding friction occurs when two surfaces slide against each other, and rolling friction occurs when a rounded object, such as a wheel, rolls over a surface. The nature of the surface affects all three types of friction.

Surface Roughness
The primary factor that influences friction between surfaces is the roughness of the surfaces in contact. When two surfaces have irregularities or roughness, the contact area between them decreases, resulting in an increase in friction. The rougher the surface, the greater the frictional force.

Surface Smoothness
Smooth surfaces have less friction compared to rough surfaces. When two surfaces are smooth, they have a larger contact area, which reduces the frictional force. This is why objects like ice or glass tend to have lower friction than rough surfaces like sandpaper.

Surface Material
The material of the surface also affects friction. Certain materials have a higher coefficient of friction, which means they generate more frictional force. For example, rubber has a higher coefficient of friction than glass, and therefore, rubber tends to produce more friction when in contact with another surface.

Surface Lubrication
Lubrication can significantly reduce friction between surfaces. When a lubricant, such as oil or grease, is applied to the surfaces in contact, it forms a thin layer that separates the surfaces and reduces friction. Lubrication is commonly used in machinery to minimize wear and tear and enhance efficiency.

Temperature
Temperature can also affect the nature of the surface and, consequently, friction. For example, ice becomes more slippery at higher temperatures due to the thin layer of water that forms on its surface. Similarly, certain materials may expand or contract with temperature changes, altering the roughness or smoothness of the surface and affecting friction.

In conclusion, the nature of the surface has a significant impact on friction. Surface roughness, smoothness, material, lubrication, and temperature all play crucial roles in determining the magnitude of friction between two surfaces in contact. Understanding these factors is essential for various applications, from designing efficient machinery to improving performance in sports and transportation.