Materiales

Estamos rodeados de objetos y todos ellos están hechos de distintos materiales. Vamos a pasar a estudiar los diferentes materiales que nos rodean.

Ver vídeo: Materials

Fuente BBC

Texto

1.

Why are hardwood timbers so called?

Because they are hard to cut.

Because they are hard to get hold of.

Because of their cell structure.

2.

Where do softwood timbers come from?

Coniferous trees

Deciduous trees

Ferrous trees

3.

What do ferrous metals contain?

Aluminium

Copper

Iron

4.

What do we call a mixture of two or more metals, or elements such as carbon?

Mixture

Compound

Alloy

5.

How many times can thermoplastics be heated and shaped?

Once

Three times

Many times

6.

What are composite materials made of?

A combination of a thermoplastic material and a suitable special agent.

A combination of a thermoset material and a suitable bonding agent.

A combination of a reinforcing material and a suitable bonding agent.

7.

What are smart materials?

Materials that react to a stimulus, such as temperature or moisture.

Materials that can be shaped many times.

Materials that change into a liquid or molten state when heated.

8.

Which of the following reacts to changes in light levels?

Thermochromic pigments

Polymorph

Photochromic pigments

9.

If a material can permanently deform in all directions without cracking, it is:

Ductile

Malleable

Elastic

10.

If a material can withstand sudden blows or shocks without breaking, it is:

Durable

Tough

Hard