Memorandum
ACTIVITY 1
- Recycling: Collection, processing and re-use of materials that would otherwise be thrown away.
- Shop – Home – Bin – Waste bag – Landfill
- Shop – Home – Recycling bins – Process of recycling
- Emblem
- Using recycled materials makes new products cost less.
Requires less energy to make products with recycled materials.
Reduces air pollution.
Decreases the amount of land needed for waste dumps.
Conserves natural resources by reducing the need for new material.
ACTIVITY 2
- Through this activity the learners will collect data and process this data. Learners must be motivated to do this at home so that they can discover how much recyclable material we throw away daily. They can copy the tables in MS Excel which will make it easy to illustrate the data in a graph.
ACTIVITY 3
- Plastics are divided into two main types – thermo softening and thermosetting. These names refer to what happens when plastic materials are subjected to heat.
- Thermo softening plastics become soft and pliable when they are heated and harden again when cooled. This process can be repeated again and again. Examples are PVC, Nylon and Polythene.
- A thermosetting plastic, on the other hand, can be moulded only once - during the manufacturing stage. These plastics are used for heat-resistant objects, such as light fittings, saucepan handles and kitchen work surfaces.
3.1 something that does not decompose naturally
- cool drink bottles, margarine containers, milk bottles, etc.
- cheap, light, durable, coloured easily, etc.
- One of the problems is that any of seven categories can be used for containers alone. For effective recycling, the different types cannot be mixed. The recycling process is also very expensive, for the plastics must first be washed, then shredded into flakes, then the flakes are melted into pellets. For health reasons, recycled plastics are rarely made into food containers.
ACTIVITY 4
4.1 It is transparent, fairly cheap to manufacture, easily formed into bottles and jars and easy to recycle. Special glasses for people with sight problems, as well as mirrors are made.
4.2 It brakes easily and has sharp edges.
4.3 Windscreens are made from laminated glass (glass sandwich) with a layer of plastic in the middle. Other kinds of strong glass include wired glass and bulletproof glass.
- If molten glass is forced through a small hole it can be drawn into very fine fibres which are known as fibreglass. These glass strands are made into thick mats which can be used for several purposes. Glass fibre is used in building boats, and for isolation in homes, etc.
ACTIVITY 5
- More than half of the world’s timber is burnt as fuel, most of it within a few kilometres of where it is felled. Half of the world’s population use wood for all their cooking and heating. The rest of the world’s timber is used in industry for building and paper-making. Most paper is made from soft woods. However, 50% of the wood pulp used to make paper comes from waste wood from the sawmill.
- Deforestation: the cutting of mature trees
Re-forestation: Replacing trees at the same rate at which they are cut down
5.2 Hardwood: Teak, Walnut, Ebony, Oak
Softwood: Pines, Spruce
- Stinkwood (or other indigenous wood)
- Tropical climate, rain throughout the year, mountain range
- In the winter the tree grows slowly and forms a dark ring while in the summer it grows fast and forms a wider and lighter ring. Together the two rings indicate one year of growth.
ACTIVITY 6
6.1 Copper, stainless steel, aluminium, brass, gold, nickel, etc.
6.2 Rods, pipe, tubes, angle-iron, I-beams, sheets
6.3 Beans, beef, corn, peas, fruit, etc.
ACTIVITY 7
7.1 Incinerators: Require less land, and will pollute ground water
Landfills: Prevent waste from blowing away, keep down odours
- Incinerators: Air pollution and expensive to operate
Landfills: Pollute ground water, uses large areas of land
- For incinerators to be profitable you need all the rubbish you can get. Municipalities therefore send all their waste to this machine to keep it running.
Situation:
How to make a lampshade:
- Mix the starch according to the instructions on the pack. Note that all the starch must be used, for it cannot be kept.
- Place the mould, e.g. a bowl, upside down and apply margarine all over it. Tear paper strips and paste them with starch around the bowl, allowing the edges of the squares to overlap.
- Tear more paper strips and cover the rest of the bowl. Tear a circle of paper and paste it on the centre to round it off neatly. Apply at least two layers of paper and allow it to dry well.
- Apply a thick layer of starch over the covered area. You can make patterns on the wet starch. Allow to dry well and slip the lampshade carefully off the bowl and allow to dry.
- You can now spray-paint the shade.
- Cut a hole in the top centre of the shade, just large enough for the flex and bulb holder to pass through.
