Grade 9 Technology Summaries Term 4 (Via Afrika): These summaries are compiled using the Via Afrika textbook's Term 3 content. The summaries are in English, with additional notes provided by the compiler.
Contents:
Topic 3: Electrical/electronic systems
Unit 1: Electrical systems and c...
, Reduce - reuse - recycle Types of plastic and their uses
• How to produce less waste:
- Reuse containers and products to Polystyrene foam
reduce toxicity.
• Can be shaped and glued easily.
- Recycle and buy products made from
• Used to make 3D objects.
recycled material.
- Create compost from organic waste. • Polystyrene = the basis for ‘foamed’ plastics.
Sample
•
•
Properties of thermoplastic
Thermoplastics are the most commonly
used plastics - range from rigid to flexible.
Thermoplastics can be bent and shaped
U3: Processing:
investigation
skills - plastics
•
•
•
Made by heating.
Thermoplastic
Can be squeezed out into long shapes - extrusion.
Melted thermoplastics can be blown into shaped
cavities to make bottles and cans - blow
Summaries after sample
when heated, making them strong and easy
to work with. moulding.
• Thermoplastics are used as heat and • The plastic is heated by a vacuum-former.
electrical insulators and as packaging • Press moulding/compression moulding – pressing
containers. materials into various shapes.
• Plastics degrade slowly, releasing toxic • Injection moulding = process where heated
fumes and polluting the air. plastic is forced into a mould.
• Manufacturing plastic produces a lot of
Thermosetting plastic • Thermoplastics can be recycled.
chemical waste.
• Hardened thermosetting plastic can’t be soften
by reheating.
• Solidifies due to a chemical reaction.
• Made by heating powder in a mould to form
object.
• Ideal for products the must resist heat, scratching
and tough handling.
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller SummariesSA. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $6.83. You're not tied to anything after your purchase.