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Disturbance is a key concept when it comes to understanding wave motion. In physics, a disturbance refers to a change or a displacement in a medium, which helps in carrying a wave through space. This concept of disturbance can be translated to simpler terms when we say that it's something temporary that causes motion or change.
When we apply this idea to the "wave" at a football game, the disturbance is the action of people standing up and then sitting down in sequence. This action is not permanent; it happens as the wave passes each part of the crowd.

• The disturbance is the sudden movement of people.
• It's temporary and shifts from one person to the next.
• It doesn't affect the whole area at once but gradually moves through the crowd.

Ultimately, disturbances are what enable waves to start, move, and continue. At a football game, the initial cheer or excitement might set off this crowd "wave," showcasing how disturbances can be powerful in creating movement.

Waves are an excellent way to visualize energy transfer since they effectively move energy across distances without transferring actual matter. In the context of a football game crowd, energy transfer can be seen as the movement and excitement that passes from one person to the next.
This energy transfer doesn't mean people are physically moving forward. Instead, it means they participate in the wave as it passes through them—standing and raising their hands, which visually looks like energy is causing a ripple effect through their actions.

• Energy in waves flows from one point to another.
• In a crowd wave, the excitement or energy fuels the motion of people standing and sitting.
• This creates a chain reaction where each person "passes" the energy on.

Empowering the "wave" through this energy transfer showcases how non-tangible excitement can be enough to cause a visual phenomenon that spreads widely.

A medium is the substance or material that carries a wave. In physics, this could be air, water, or any other substance that allows waves to travel. **In terms of the football crowd wave**, the medium is the crowd itself.
The medium is critical because, without it, there would be no way for the wave to progress. For the crowd wave:

• The people act as the medium—without their participation, the wave can't form or continue.
• Each person essentially acts like a particle in a medium, responding sequentially to energy transfer.
• Though no one person moves a great distance, their collective action enables the wave to move through the entire crowd.

The crowd's role as a medium demonstrates how waves must rely on their environment to travel and manifests the physical principles of wave motion in a lively and engaging way.