Science: The Power of Wind and Rubber

Hello everyone! In this chapter, we will learn about the forces that "wind" and "rubber" exert to move objects around us.
From sailboats gliding across the sea to paper poppers launched by rubber bands... behind these everyday phenomena hide fascinating scientific principles. Let’s explore them together!

1. The Power of Wind

When wind hits an object, it can push it into motion. How does changing the strength of the wind affect the way an object moves?

Wind Speed and Distance Traveled

By using a fan to blow wind at a sailboat model, we can discover the following:

  • When using a gentle breeze: The car only travels a short distance.
  • When using a strong wind: The car travels a long distance (further away).

【Key Point】
The stronger the force of the wind, the greater its power to move an object, making it travel further and faster.

Analogy: Have you ever felt like your body was being pushed backward while holding an umbrella on a windy day? That’s because the wind’s "pushing force" against the umbrella is strong. On the other hand, you don't feel that with a light breeze. The same thing happens in our experiment!

Fun Fact:
Large sailing ships used to harness this wind power with massive sails to travel across the world's oceans. Even today, this principle is used in "wind power generation" to create electricity using the energy of the wind.


2. The Power of Rubber

Rubber has a property where it "tries to return to its original shape after being stretched." Let’s use this restorative force to move objects.

Stretching Distance and Distance Traveled

Using a rubber-band-powered car, let's experiment by changing how far we stretch the rubber band.

  • When the rubber is stretched a little: The car travels a short distance.
  • When the rubber is stretched a lot: The car travels a long distance.

【Key Point】
The further you stretch a rubber band, the stronger its force to return to its original shape becomes, resulting in a greater power to move objects.

Number of Rubber Bands and Moving Force

What happens if we increase the number of rubber bands, rather than just changing the length?
By increasing the number of bands—using two or three instead of just one—their restorative forces combine, allowing you to move the car with much greater force.

Analogy: Think about a toy slingshot. If you pull the rubber back just a little and let go, the projectile won't go far. But if you pull it back as far as you can, it flies off with great speed. That is the power of rubber in action!


3. Common Mistakes in Experiments (Be Careful!)

Let's check some common pitfalls to avoid during tests and experiments.

× Mistake: "The more you stretch a rubber band, the further it will fly, forever."
○ Correct: Rubber bands have a "limit to how much they can stretch." If you stretch them beyond their limit, the rubber might snap, or the car might break. It is important to change the length "within a safe and designated range" during experiments.

× Mistake: "The car will move forward even in a headwind."
○ Correct: The force of the wind acts in the direction that the wind is blowing. To move a sailboat forward, you need to have the wind blowing from behind it. Always observe the direction of the wind carefully!


4. Summary of this Chapter

Finally, let's review the most important points!

  • The stronger the wind, the further the object moves.
  • The further you stretch the rubber, the further the object moves.
  • The more rubber bands you use, the greater the force becomes.

“It might seem difficult at first, but don't worry!”
Actually playing with a rubber band or fanning yourself with a paper fan to feel the "resistance" is the quickest way to understand these concepts. Try looking for the power of wind and rubber in the world around you!