Concept explainers
(a)
The frequency of small oscillation.
Answer to Problem 19.89P
The frequency of small oscillation is
Explanation of Solution
Given:
Length of inverted pendulum is
Mass of inverted pendulum is
Spring constant is
Concept used:
Write the expression for the potential energy for the maximum displacement position.
Here,
Substitute
As
Substitute
Here,
Kinetic energy of inverted pendulum at maximum displacement is
Write the expression for the kinetic energy at maximum velocity position.
Here,
Substitute
Substitute
Here,
The potential energy of the system at maximum velocity position is 0.
Write the expression for the conservation of energy.
Write the expression for the natural frequency of oscillation.
Here,
Calculation:
Substitute
Simplify the above expression for
Substitute
The frequency of small oscillation is
Conclusion:
Thus, the frequency of small oscillation is
(b)
The smallest value of
Answer to Problem 19.89P
The smallest value of
Explanation of Solution
Concept used:
For the oscillation to occur, the value of natural frequency should be real.
Calculation:
Substitute
The smallest value of
Conclusion:
Thus, the smallest value of
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Chapter 19 Solutions
Vector Mechanics for Engineers: Dynamics
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