2.1 How does the nature of a surface on which an object is being moved affect the frictional force experienced by the object? 2.2 State the two factors on which friction depends.
Answer (1)
2.1 The nature of a surface affects the frictional force experienced by an object because of the texture and material of the surface. A rough surface increases the frictional force because there are more irregularities or 'peaks and valleys' that interlock with the object's surface, making it harder to move. In contrast, a smooth surface has fewer irregularities, resulting in less friction, and thus the object can slide more easily. Additionally, the type of material can also influence friction; for example, rubber on concrete will have more friction than a piece of ice on metal due to differing resistive properties.
2.2 Friction depends mainly on two factors:
The nature of the surfaces in contact: As explained, smoother surfaces tend to create less friction, while rougher surfaces create more.
The normal force pressing the two surfaces together: This is effectively the weight of the object, which influences friction. The greater the normal force (for example, when an object is heavier), the greater the frictional force, since more force is pressing the surfaces into each other.
