SQA Higher Physics Practice Exam – Practice Test & Study Guide

When a system is driven at its natural frequency, it experiences resonance. This phenomenon is characterized by a dramatic increase in amplitude of oscillation in systems such as mechanical structures, electrical circuits, or even sound waves. At this frequency, the energy supplied to the system aligns perfectly with the system's natural tendency to oscillate, resulting in the transfer of energy in a manner that significantly enhances the oscillation's intensity.

Resonance happens because the driving force matches the system's inherent oscillation frequency, effectively causing the system to absorb energy efficiently. This is seen in various practical examples, such as swings, musical instruments, and bridges where the structure can oscillate vigorously if external forces are applied at the correct frequency.

The other phenomena listed do not pertain directly to the amplification of oscillations at the natural frequency of a system. Damping refers to the gradual loss of amplitude in an oscillating system, while interference deals with the interaction of waves. Refraction involves the bending of waves as they pass through different mediums, rather than the amplification of oscillations in a driven system.