Concept explainers
ToCalculate: Whether there are any values for the coefficients of static friction.
Answer to Problem 74P
There are values for the coefficients of static friction as below.
Explanation of Solution
Given information :
Length of the beam
Radius of the cylinder
Mass of the beam
Mass of the cylinder
The coefficient of static friction between beam and cylinder
The coefficients of static friction between the cylinder and the floor, and between the beam and the floor, are not zero.
Formula used :
Weight of a body can be obtained by:
Where, m is the mass and g is the acceleration due to gravity.
Friction force is:
Where,
Calculation:
The forces that act on the beam are its weight
The force of the cylinder acting along the radius of the cylinder
The normal force of the ground
Friction force
The forces acting on the cylinder are its weight
The force of the beam on the cylinder acting radially inward
The normal force of the ground on the cylinder
The force of friction
Choose the coordinate system as in the below given figure and apply the conditions for rotational and translational equilibrium.
Express
Express
Apply
Solve for
Apply
Apply
Apply
Solve for
Apply
And
Conclusion:
There are values for the coefficients of static friction. They are given as below.
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Chapter 12 Solutions
Physics for Scientists and Engineers
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