Resonance
Resonance explained in an easy to understand way:
Imagine trying to push someone on a swing; if you push at the right moment, they'll go higher and higher. This is similar to resonance, where an object increases its vibration amplitude when another object vibrates at the same frequency. Just as timing your pushes with the swing's natural rhythm makes it soar higher, when two objects share the same vibration frequency, one can amplify the other's motion, leading to increased energy and movement.
Practice Version
Resonance: An increase in the vibration amplitude of an object, caused by another object vibrating at the same frequency. Resonance occurs when an object vibrates at the same natural frequency as another, causing it to vibrate more strongly.