Unit 5.1 Alevel DT AQA Composites

Materials are combined to make composites because:

• they have improved properties compared to individual materials.

• they are easier to recycle than pure materials.

• they are always cheaper to produce than single materials.

• they are naturally found in combined forms.

The properties that make CFRP (carbon fibre reinforced plastic) suitable for making wind turbines are:

• High strength-to-weight ratio and corrosion resistance

• High electrical conductivity and low cost

• Low density and high thermal expansion

• Brittleness and poor fatigue resistance

Which of the following are properties of concrete?

• High compressive strength

• High electrical conductivity

• Low durability

• High flexibility

Very little concrete is traded internationally because it can be locally sourced, which reduces CO2 emissions.

• True

• False

In steel reinforced concrete it is important that steel expands and contracts at the same rate as concrete because:

• it prevents cracking and structural failure in reinforced concrete structures.

• it makes the structure heavier.

• it decreases the cost of construction.

• it allows for more decorative designs.

The drawbacks of using solid timber for flooring as opposed to engineered floor boards include:

• Greater susceptibility to moisture and temperature changes

• Higher resistance to moisture and temperature changes

• Lower installation cost

• More stability in varying climates

All manufactured boards are composites.

• True

• False

• Only some are composites

• None are composites

Glulam can be used as an alternative to steel to make which of the following?

• Beams

• Bridges

• Archways

• All of the above

Composites could be used to reduce earthquake damage by:

• increasing the flexibility and strength of structures

• making buildings heavier to resist shaking

• allowing cracks to form more easily in walls

• reducing the cost of construction materials

Composites could be used to improve the performance of a sportsperson by:

• making equipment lighter and stronger

• increasing the weight of equipment

• reducing the flexibility of equipment

• making equipment more prone to damage