Young Engineers: Class 3 Catapult - Sturdy and Fun DIY Engineering Activity for Kids

Summary

In this video, Lance demonstrates how to construct a class 3 catapult using craft sticks, cubes, and rubber bands. He explains the lever principle behind it, detailing each step from assembling the base to attaching the arm and rubber bands. Lance also shares tips for optimizing the catapult's performance by experimenting with different projectiles and adjusting the arm's length, emphasizing the impact of projectile characteristics and the arm's potential speed due to its distance from the fulcrum.

Takeaways

• 🔨 The class 3 catapult is a demonstration of a class 3 lever, utilizing a fulcrum, load, and effort.
• ✂️ Start by cutting or breaking three craft sticks in half using pliers or wire cutters.
• 🔗 Connect two regular craft sticks with one half stick piece and glue additional sticks to form the base structure.
• 🔩 Build triangular supports on the sides of the base and add half stick pieces to the top of the triangles.
• 🏗️ Create a catapult arm by gluing two craft sticks together with a third one in the middle.
• 🔄 Attach the arm to the base using a thin dowel as a hinge, ensuring the arm can move freely.
• 🔁 Loop rubber bands around the catapult arm to provide the necessary tension for launching.
• 🎯 Attach a plastic cup to the end of the catapult arm using both glue and tape for stability.
• 🚀 Experiment with different projectiles to find the optimal density, weight, shape, and size for distance.
• ⚖️ Adjust the length of the catapult arm to increase speed and performance, considering the trade-off with inertia.

Q & A

What is the main concept demonstrated in the video?

The video demonstrates how a class 3 lever works using a catapult as an example.

What materials are needed to build the catapult as described in the script?

The materials needed include craft sticks, hot glue, a pair of pliers or wire cutters, a thin dowel, rubber bands, and a plastic cup.

How many craft sticks are cut in half at the beginning of the project?

Three craft sticks are cut in half at the beginning of the project.

What is the purpose of the gap between the two cubes with holes on the base of the catapult?

The gap between the two cubes with holes is left open to accommodate the dowel that will act as the hinge for the catapult arm.

How is the catapult arm constructed?

The catapult arm is constructed by creating a beam that's two craft sticks long, connected in the middle with a third craft stick, and repeating the process once more.

What role does the thin dowel play in the catapult's mechanism?

The thin dowel acts as a hinge, allowing the catapult arm to move up and down.

How are the rubber bands attached to the catapult arm?

The rubber bands are looped around the catapult arm, pulled under the stop bar at the top, stretched out, and looped back over the arm again.

What is recommended for the catapult's projectile, and why?

Foam cubes are recommended as projectiles because they are dense enough to go far but not likely to break anything, making them suitable for indoor use.

What factors can affect the performance of the catapult when launching projectiles?

The density, weight, shape, and size of the projectile can significantly affect the catapult's performance.

How can the length of the catapult arm impact the catapult's effectiveness?

A longer catapult arm can allow for faster movement due to greater distance from the fulcrum, but it may also require more energy to move and might need additional or different rubber bands for optimal performance.

What are two things viewers can experiment with to improve their catapult's performance?

Viewers can experiment with different projectiles and the length of the catapult arm to improve performance.