Question

State whether the following statements are true or false. Provide a brief justification for your answer.

Answer 1

Answer:

[a] False.

[b]. True

[c]. false.

[d]. true.

[e]. true.

Explanation:

NB: SDOF simply means Simple Degree Of Freedom, that is to say it is a system that can be solved by differential equation such as the second order and the single differential equation.

So, the question asked us to determine if each of the scenario is true or false.  

a. Consider a SDOF system with Coulomb damping. When displaced from the equilibrium position and released, the mass may not move at all.

ANSWER:  FALSE.

REASON: The mass moved a little bit When displaced from the equilibrium position and released.

b. Consider a SDOF system with an ideal viscous damper. When displaced from the equilibrium position and released, the mass will always undergo oscillatory motion.

ANSWER: TRUE

REASON:  for an ideal viscous damper. When displaced from the equilibrium position and released, the mass will always undergo oscillatory motion.

c. The damped natural frequency of a system is always greater than the undamped natural frequency

.

ANSWER:  FALSE

REASON:  The damped natural frequency of a system is always greater than the undamped natural frequency

d. For an undamped system undergoing a harmonic forcing, the amplitude of the response approaches zero as the forcing frequency becomes very high.

ANSWER: TRUE

REASON:  the amplitude of the response approaches zero as the forcing frequency becomes very high for  undamped system undergoing a harmonic forcing

e. The amplitude of free response of SDOF system with Coulomb damping decreases

ANSWER: TRUE

REASON:  amplitude of free response of SDOF system with Coulomb damping decreases