EIT - Engineer In Training Dynamics and Vibrations Questions and Answers

Question 1

A 15 kg mass is attached to a spring with a stiffness constant (k) of 3750 N/m. Assuming the system is undamped, what is most nearly the natural frequency (ωn) of the system?

Accepted Answer

15.8 rad/s

Answer

250.0 rad/s

Answer

0.25 rad/s

Answer

25.0 rad/s

Question 2

A 2 kg block is initially at rest on a horizontal surface. A constant horizontal force of 30 N is applied to the block, which moves it a distance of 5 m. If the coefficient of kinetic friction between the block and the surface is 0.4, what is the final velocity of the block? (Use g = 9.81 m/s²)

Accepted Answer

11.3 m/s

Answer

12.7 m/s

Answer

10.1 m/s

Answer

8.8 m/s

Question 3

Which of the following physical quantities represents a body's resistance to angular acceleration?

Accepted Answer

Mass Moment of Inertia

Answer

Mass

Answer

Angular Momentum

Answer

Linear Momentum

Question 4

A 1,200 kg car traveling at 20 m/s collides with a stationary 1,800 kg truck. The two vehicles lock together after the collision. What is the velocity of the combined mass immediately after this perfectly inelastic collision?

Accepted Answer

8.0 m/s

Answer

12.0 m/s

Answer

13.3 m/s

Answer

20.0 m/s

Question 5

Resonance in a mechanical system is a phenomenon that occurs when:

Accepted Answer

The forcing frequency is very close to the system's natural frequency.

Answer

The damping ratio of the system is exactly one.

Answer

The forcing frequency is an integer multiple of the system's natural frequency.

Answer

The system has zero damping.

Question 6

In the study of single-degree-of-freedom vibrating systems, a critically damped system is one that:

Accepted Answer

Returns to its equilibrium position in the shortest possible time without oscillating.

Answer

Oscillates indefinitely with a constant amplitude.

Answer

Returns to its equilibrium position very slowly without oscillating.

Answer

Oscillates with an amplitude that gradually decreases to zero.