Concept explainers
Give three important “laws” that characterize frictional interactions between two Solids sliding past one another.
The three important “laws” that characterize frictional interactions between two solids sliding past one another.
Answer to Problem 1EA
The three laws of friction are
1. When a body is moving the frictional force is directly proportional to the normal contact force acting on the body.
2. The friction does not depend on the area of contact between the two bodies sliding past one another but depends on the type of surface in contact.
3. The value of coefficient of static friction is slightly more than the coefficient of kinetic friction.
Explanation of Solution
The laws are summarized which will characterize the two solid bodies sliding past each other.
First law:
When a body is moving the frictional force is directly proportional to the normal contact force acting on the body.
Second law:
The friction does not depend on the area of contact between the two bodies sliding past one another but depends on the type of surface in contact.
Third law:
If two solid bodies slide over each other, then the force of friction is given by
Where,
If two solid bodies do not slide over each other then the force of friction is given by
Where,
Conclusion:
The three laws of friction are
1. When a body is moving the frictional force is directly proportional to the normal contact force acting on the body.
2. The friction does not depend on the area of contact between the two bodies sliding past one another but depends on the type of surface in contact.
3. The value of coefficient of static friction is slightly more than the coefficient of kinetic friction.
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Chapter 2 Solutions
Inquiry into Physics
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