Concept explainers
(a)
Minimum value of coefficient of static friction between the collar and rod at
Answer to Problem 12.128RP
Minimum value of coefficient of static friction between the collar and rod is 0.454.
Explanation of Solution
Given information:
Mass of the collar C, m=200 gm or 0.2 kg.
Angular rotation of rod,
Position of block E,
Calculations:
AB is the axis of rotation and collar C slide on semicircular rod. So, the distance of collar C from the axis AB,
Acceleration of the collar,
Equilibrium force along x direction,
Equilibrium force along y direction,
(b)
Minimum value of coefficient of static friction between the collar and rod at
Answer to Problem 12.128RP
Minimum value of coefficient of static friction between the collar and rod is 0.179.
Explanation of Solution
Given information:
Mass of the collar C, m=200 gm or 0.2 kg.
Angular rotation of rod,
Position of block E,
Calculations:
AB is the axis of rotation and collar C slide on semicircular rod. So, the distance of collar C from the axis AB is
Acceleration of the collar,
For the value of
For downward impending motion,
Equilibrium force along y direction,
Equilibrium force along normal direction,
Equating equation 1 and equation 2,
For upward impending motion,
Equilibrium force along y direction,
Equilibrium force along normal direction,
Equating equation 4 and equation 5,
(c)
Minimum value of coefficient of static friction between the collar and rod at
Answer to Problem 12.128RP
Minimum value of coefficient of static friction between the collar and rod is 0.218.
Explanation of Solution
Given information:
Mass of the collar C, m=200 gm or 0.2 kg.
Angular rotation of rod,
Position of block E,
Calculations:
AB is the axis of rotation and collar C slide on semicircular rod. So, the distance of collar C from the axis AB,
Acceleration of the collar,
For the value of
For downward impending motion,
Equilibrium force along y direction,
Equilibrium force along normal direction,
Equating equation 1 and equation 2,
For upward impending motion,
Equilibrium force along y direction,
Equilibrium force along normal direction,
Equating equation 4 and equation 5,
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Chapter 12 Solutions
Vector Mechanics for Engineers: Dynamics
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