Bend That Bar
Bending of an I-beam.Copyright 2007 Avenafatua, Wikimedia Commons http://commons.wikimedia.org/wiki/File:I_beam_bending0.png
Students learn about material properties, and that engineers must consider many different materials properties when designing. This activity focuses on strength-to-weight ratios and how sometimes the strongest material is not always the best material.
Finding the best engineering solution for a given design challenge requires a delicate balance between many factors such as weight, strength, cost, performance, safety and ethics. For example, the strongest design might be too expensive, or the safest design might be too heavy. An engineer's final design is a compromise between all considered criteria. The strength-to-weight ratio is an important balance engineers must find when designing airplanes because we want airplanes to be very strong, but also as light as possible.
After this activity, students should be able to:
- Explain the significance of a material's strength-to-weight ratio.
- Compare and contrast how useful a material is for a project based on its strength, weight and other properties.
- Measure and record mass, height and distance of a bending bar.