Concept explainers
(a)
The co-efficient of static friction between the floor and the refrigerator.
(a)
Answer to Problem 43P
The co-efficient of static friction between the floor and the refrigerator is
Explanation of Solution
Write the expression for maximum force of static friction.
Here,
Write the expression for normal force acting on the downward force of gravity on the refrigerator.
Here,
Substitute equation (II) in equation (I).
Conclusion:
Substitute
Therefore, the co-efficient of static friction between the floor and the refrigerator is
(b)
The co-efficient of kinetic friction between the refrigerator and the floor.
(b)
Answer to Problem 43P
The co-efficient of kinetic friction between the refrigerator and the floor is
Explanation of Solution
After the refrigerator starts moving, there is acceleration and the frictional becomes kinetic friction.
Write the expression from Newton’s second law of motion.
Here,
Write the expression for kinetic frictional force.
Here,
Substitute equation (IV) in equation (III).
Write the expression from kinematics equation of motion.
Here,
Substitute
Conclusion:
Substitute
Substitute
Therefore, the co-efficient of kinetic friction between the refrigerator and the floor is
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Chapter 3 Solutions
College Physics, Volume 1
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