Which term describes the decrease of a wave's amplitude over time?

Which term describes the decrease of a wave's amplitude over time?

• A. Interference
• B. Frequency
• C. Resonance
• D. Damping

Answer: (D)

Damping describes the decrease of a wave’s amplitude over time because energy is being lost to the surroundings, such as through friction, air resistance, or internal material losses. As energy dissipates, the oscillations fade away, often following an exponential decay. In a vibrating string or a swinging pendulum, you see the motion die down gradually—the amplitude gets smaller while the system still oscillates until it settles. The amount of damping determines how fast this decay happens and whether the system returns to rest quickly or lingers before stopping. Interference involves how waves combine and either reinforce or cancel each other, producing patterns of varying amplitude in space, but it isn’t about the gradual fading of a single wave over time. Frequency is the rate at which the wave cycles per second, not how its amplitude changes. Resonance is about achieving large amplitudes when a driving force matches the system’s natural frequency, not the general decrease of amplitude with time.

Damping describes the decrease of a wave’s amplitude over time because energy is being lost to the surroundings, such as through friction, air resistance, or internal material losses. As energy dissipates, the oscillations fade away, often following an exponential decay. In a vibrating string or a swinging pendulum, you see the motion die down gradually—the amplitude gets smaller while the system still oscillates until it settles. The amount of damping determines how fast this decay happens and whether the system returns to rest quickly or lingers before stopping.

Interference involves how waves combine and either reinforce or cancel each other, producing patterns of varying amplitude in space, but it isn’t about the gradual fading of a single wave over time. Frequency is the rate at which the wave cycles per second, not how its amplitude changes. Resonance is about achieving large amplitudes when a driving force matches the system’s natural frequency, not the general decrease of amplitude with time.