Grade 8 Technology Term 2 - Materials and Forces

Vocabulary flashcards covering material development, recycling processes, packaging types, and structural forces based on Grade 8 Technology notes.

Substitute

Something that gets used in place of something else, often to assist in conserving natural materials.

Human-made products

Materials often made from chemicals that are used in place of natural materials.

Plastics

A byproduct of the petrochemical industry that is fairly cheap to manufacture and is a major contributor to the litter problem in South Africa.

Recycle

To use an item again by taking material from an item that might have been thrown away and turning it into a new product.

Biodegradable

A product that can be broken down into its fundamental elements and re-absorbed by the Earth over a short period of time.

Corn-starch

A renewable source of energy used to make biodegradable products.

Cellulose fibres

Fibres used for making paper, sourced in South Africa from trees, wood chips, sawmills, used paper, and bagasse.

Pulp

A substance formed during the recycling process by soaking paper in water and shaking it to release cellulose fibres.

Froth flotation

An environmentally friendly method of removing ink from pulp where air is hit into the pulp so ink particles stick to air bubbles and form a foamy scum.

Paper board

A strong material made from layers of cellulose fibres arranged at right angles to each other, using both recycled and new pulp.

Corrugated card

A strong and cheap packaging material consisting of two outer liner boards and an inner wavy layer.

Reinforced concrete

Concrete that has steel rods, bars, or mesh embedded inside it to help it withstand the forces of tension and shear.

Plywood

A material made of three or more thin layers of wood glued together with the grains arranged in alternate directions.

Stiffness

The ability of a beam to resist the force of bending, which is proportional to its $\text{breadth} \times \text{depth}^3$.

Forces on Materials

The five forces that act on materials: tension, compression, bending, torsion, and shear.