VR Tour For Std. 8 Ch. 12. Friction
What's Included in Virtual tour of this chapter
Friction always opposes the motion because it acts in the opposite direction to motion. Force of friction arises due to contact between two surfaces. If there is no contact between two surfaces there would be no friction. When two surfaces are interlocked, the friction will be great. The wear and tear of materials are caused by friction. Thus, there are advantages and disadvantages to this force. There are two types of Friction- Rolling and sliding Friction. At last, we will learn how friction is exerted in fluids and gases.
Virtual tour 1: Introduction of Friction
“Friction opposes the relative motion between two surfaces in contact”. Friction depends on the nature of surfaces in contact. The presence of irregularities on rough and smooth surfaces restricts the easy movement of the object and so the effort to move the object will be more. The force which acts opposite to the direction to the motion of an object is called the frictional force.
Virtual tour 2: The force of friction
When two rough surfaces come in contact, then the degree of friction between them is large as the interlocking between rough surfaces is too much. Whereas, when two smooth surfaces come in contact, then the degree of friction between them as small as the interlocking between smooth surfaces is less. We will perform an activity to learn about how this occurs.
Virtual tour 3: The factors affecting Friction
Now we will learn about what are the factors affecting friction. It will depend on the roughness/smoothness of the object and the surface. We will learn about this more by performing an activity on grassland and a sandy surface.
Virtual tour 4: The Advantages and Disadvantages of Friction
Friction produces unnecessary heat which leads to wastage of energy. It also slows down the motion of moving objects because it acts in an opposite direction. It is the main reason which causes wear and tear of machines. Therefore as we know that friction is useful in many cases but it is harmful as well. Therefore it is called a necessary evil.
Virtual tour 5: Increasing and Reducing Friction
In this virtual tour, we will perform an activity that will show us how Friction can be increased by increasing the roughness of the two surfaces in contact. In the same way, friction can be reduced by increasing the smoothness or decreasing the roughness of the two surfaces.