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## #1 2015-02-02 21:52:30

David
Member
From: Bumpkinland
Registered: 2014-04-23
Posts: 3,136

### I need help with a presentation

I was assigned to present a presentation for my math class about Scale Drawings that needs to last 30-45 minutes. But I can't think of anything that would last that loooong... Easy topic to be honest.

Meaningless, meaningless, Everything is meaningless! - Ecclesiastes 1:2

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## #2 2015-02-02 22:07:00

bob bundy
Registered: 2010-06-20
Posts: 8,226

### Re: I need help with a presentation

hi Chris,

Can you use a projector ?  Whiteboard ?  Blackboard ? ...

You can show centres of enlargement / negative enlargements / fractional 'enlargements'

Scale factors for length / area / volume

Bob

Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

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## #3 2015-02-02 22:08:42

David
Member
From: Bumpkinland
Registered: 2014-04-23
Posts: 3,136

### Re: I need help with a presentation

I can use a whiteboard and some mamila card diagrams only.
I want to try and present something not in the syllabus. I can't think of anything.

Meaningless, meaningless, Everything is meaningless! - Ecclesiastes 1:2

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## #4 2015-02-02 22:22:59

bob bundy
Registered: 2010-06-20
Posts: 8,226

### Re: I need help with a presentation

Couple of ideas:

"I've made a miniature figure; now how much more will it take to make a lifesize model ?"  http://www.sculpture.net/community/showthread.php?t=479

The presenter James May had a series on TV about toys.  He had made plastic airplane kits as a child and wanted a full size one.  section 3.1 http://en.wikipedia.org/wiki/James_May' … isode_1.29

Why did the wings break ?

If I get any more I'll post again.

Bob

Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

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## #5 2015-02-02 22:24:39

David
Member
From: Bumpkinland
Registered: 2014-04-23
Posts: 3,136

### Re: I need help with a presentation

Thanks for the link, will read it later. Now I have to get my room tidy.

Meaningless, meaningless, Everything is meaningless! - Ecclesiastes 1:2

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## #6 2015-02-02 22:26:34

bob bundy
Registered: 2010-06-20
Posts: 8,226

### Re: I need help with a presentation

Bob

Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

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## #7 2015-02-03 01:32:13

bob bundy
Registered: 2010-06-20
Posts: 8,226

### Re: I need help with a presentation

Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

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## #8 2015-02-03 01:43:43

David
Member
From: Bumpkinland
Registered: 2014-04-23
Posts: 3,136

### Re: I need help with a presentation

Hi Bob,
Room is tidy.
Thanks for the ideas! appreciated it.
Hmm... Pantograph... Might be something that I could talk about that is interesting...
Chris

Meaningless, meaningless, Everything is meaningless! - Ecclesiastes 1:2

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## #9 2015-02-03 02:08:02

bob bundy
Registered: 2010-06-20
Posts: 8,226

### Re: I need help with a presentation

You could make one (on a board that hangs over the whiteboard and with the centre fixed by a screw*) , and also show why it works.

Bob

* The trick for a successful drawing is to eliminate slippage.  So fix the centre and pin the paper to the board so it cannot slip.  Find some simple drawings that you can enlarge.

Can you see how to make the scale factor variable ?

Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

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