3.10 How Do Engineers Improve Materials?

Building a shelter in the woods is an example of

• a problem with different solutions.

• a constraint that limits some options.

• the properties you want to have.

• the materials that you will use.

Not having any nails would be an example of a ____ when building a shelter.

• criteria

• problem

• constraint

• material

Which of the following best defines criteria?

• the properties that you want

• the problem you need to solve

• the material that you have

• the limit to certain things

When engineers begin designing a tool, they first must

• identify the constraints.

• define the problem.

• choose the best material.

• identify the criteria.

Which of the following is an example of a constraint when designing a tool?

• the material doesn’t rust

• the material is easy to clean

• the material is expensive

• all of these

________ can help narrow down the choice of materials for a specific job.

• Both criteria and constraints

• Criteria but not constraints

• Not criteria but constraints

• Neither criteria or constraints

Engineer invent completely new materials by

• mixing known materials.

• making materials lighter.

• rearranging particles.

• identify certain properties.

Which of the following was created by rearranging particles to create a new material?

• Aluminum Foil

• Carbon Fiber

• Stainless Steel

• all of these

An engineer has to test different ways of making a new material because sometimes a material

• is expensive to make.

• is difficult to make.

• has unwanted properties.

• all of these

Carbon fiber is a good material for bikes because it is strong and_____.

• lightweight

• not expensive

• easy to clean

• does not rust

Answer explanation

In addition to racing bikes, carbon fiber is also used in aircrafts and racecars.