Final answer:
In an earthquake, buildings with a lower natural frequency may perform better because they are less likely to resonate with the high frequencies of seismic waves. However, the effects of resonance and interference can vary with location, building design, and frequency of the earthquake waves. Therefore, the concept of natural frequency is crucial to earthquake-resistant design, but a multi-faceted approach is necessary to ensure structural integrity.
Step-by-step explanation:
When it comes to whether a lower natural frequency is better in an earthquake, it is important to consider the phenomenon of resonance. During an earthquake, buildings can vibrate at a frequency that matches their natural frequency of vibration. This can lead to resonance, amplifying the motion and potentially causing the building to collapse. Structures with a lower natural frequency tend to shake less since earthquakes typically have higher frequencies. However, the entire scenario is quite complex due to factors such as standing waves and constructive and destructive interference which might cause different effects at different locations and altitudes.
It is also observed that large, flat roofs that are only supported at the edges, such as those found in gymnasiums, supermarkets, and churches, may resonate with the earthquake's frequencies leading to collapse - underscoring the importance of natural frequency in a structure's design. Furthermore, constructive interference can amplify seismic waves as they reflect off denser subsurface rocks, which might cause damage to areas farther from the epicenter while sparing areas closer to it.