Strawkets and Weight
Students investigate the effect that weight has on rocket flight. They construct a variety of drinking straw-launched rockets—"strawkets"—of different weights. Specifically, they observe what happens when the weight of a strawket is altered by reducing its physical size and using different construction materials. They also they determine the importance of weight distribution in rockets. In the continuing hypothetical story for this unit, what students learn about rocket weight adds to their background understanding in their effort to help Tess launch a communication satellite.
Figure 1. A strawket.
When designing rockets, one important consideration is weight. The more a rocket weighs, the more energy or thrust is required to launch it. Engineers aim to make rockets as light as possible while still making them strong—and as inexpensively as possible. If a rocket structure is too light, it will not be strong enough to withstand the stress forces of a launch. Engineers sometimes must compromise between the rocket weight and the rocket materials cost. They also consider a rocket's the weight distribution to make sure it moves as intended.
After this activity, students should be able to:
- Discuss what affects the weight of a rocket.
- Explain why the weight distribution of a rocket is important.
- Identify some factors that engineers must consider when designing rockets.