Final answer:
Increasing a building's mass does indeed increase its fundamental period of vibration, which can be beneficial in preventing resonance with seismic activity.
Step-by-step explanation:
The statement that increasing a building's mass increases its fundamental period of vibration is true. This is rooted in the principles of physics that describe the behavior of oscillating systems. The period of a structure's vibration is dependent on its mass and stiffness, with more massive structures generally having longer periods. This is similar to how a heavy person on a diving board bounces up and down more slowly compared to a lighter one. In the context of a building, when seismic activity occurs, taller buildings that act like inverted pendulums can have longer periods due to increased mass, such as in the case of tuned-mass dampers like liquid-column mass dampers used in structures like the Comcast Building. When we consider seismic waves and their interaction with buildings, the condition known as resonance occurs when the frequency of the seismic waves matches the natural frequency of a building, which can be disastrous. The aim of adding mass dampers is, therefore, to alter the natural frequency and prevent this destructive resonance.