What phenomenon occurs when a system absorbs energy at its natural frequency?

When a system absorbs energy at its natural frequency, the phenomenon that occurs is resonance. This process involves a system that oscillates at maximum amplitude because the driving frequency matches the system's natural frequency.

In simpler terms, every physical system has its own natural frequency, which is the frequency at which it tends to oscillate when not influenced by external forces. When an external force is applied at this specific frequency, the energy from the force is efficiently transferred to the system, resulting in a significant increase in amplitude of the oscillation.

Resonance is commonly observed in various systems across different fields, such as in mechanical systems like swings, musical instruments, and even in buildings during earthquakes. This concept is crucial because it illustrates how energy transfer can be maximized under certain conditions, leading to potentially dramatic effects.

The other concepts mentioned, such as frequency modulation, harmonic oscillation, and phase shift, do not specifically describe the energy absorption at a system's natural frequency. Rather, they pertain to different aspects of wave behavior and oscillatory systems. Frequency modulation relates to varying the frequency of a signal, harmonic oscillation refers to oscillations that occur at harmonics of a fundamental frequency, and phase shift involves a change in the phase of a