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Mathematics

Perimeter, area and volume

Educator section

Memorandum

21.1.2

21.2.3

  • 6; 8; 12
  • 7

21.2.6

21.2.7

a) right-angled or rectangular prism

b) cuboid

a)

b)

Leaner section

Content

Activity: nets [lo 3.4, lo 3.7]

21.2 NETS:

21.2.1 For this activity please bring a cardboard box of any size to school. Cut it open (be careful!) so that you can unfold it flat on your table or desk. Now count how many edges, vertexes and faces it has.

21.2.2 Did you know?

When we cut a cube or any other form open and lay it flat (see sketch) we call the spread-out cube/figure the net of the cube/figure. The dotted lines indicate the folds.

21.2.3 Look carefully at the following net of a cube. Can you draw one or two more nets that will differ from this one?

21.2.4 Now trace the net of the cube above neatly and accurately. Now fold your own cube. Use sticky tape to join the edges together

Complete: A cube has._________ faces, _________ vertexes and _________ edges.

21.2.5 Now modify your cube into a di. Compare this with an actual di if you don’t know where to make the dots!

What is the total number of dots on the opposite faces of a di? __________________

21.2.6 Can you complete the following nets? Loosen the edges of your dice and fold it flat to help you.

a)

b)

c)

d)

e)

21.2.7 Bring any empty cereal box from home to school. Cut it open along the edges and lay it flat. Now answer these questions:

a) What do we call this box you have brought along?

_____________________________________________________________________

b) Can you give a synonym for your answer at (a) ?

_____________________________________________________________________

c) Now draw the net of the cereal box that you have cut open.

d) Can you also draw the net of a rectangular prism in another way?

21.2.8 CLASS DISCUSSION

Which of the following nets, do you think, a manufacturer would rather use? Motivate!

A

B

_____________________________________________________________________

_____________________________________________________________________

_____________________________________________________________________

_____________________________________________________________________

21.2.9 BRAINTEASER!

Two parts of the nets of the following figures are missing. Can you draw them in?

a)

b)

22. Time for self-assessment

  • Colour in the face that is true of your understanding of the work covered::
  • Colour in the face that is true of your understanding of the work covered::
I can explain the difference between 2 and 3 dimensional objects.
I can explain the following concepts:
  • edge
  • vertex
  • face
  • cube
  • rectangular prism
  • layout
I can identify and name different 3 dimensional forms.
I can calculate the number of sides of a 3 dimensional figure.
I can calculate the number of vertices of a 3 dimensional figure.
I can calculate the number of sides of a 3 dimensional figure.
I can draw a cube from different angles.
I was able to complete the di layouts successfully.
I can draw more than 1 layout of a rectangular prism.

Assessment

Learning Outcome 3: The learner will be able to describe and represent characteristics and relationships between two-dimensional shapes and three-dimensional objects in a variety of orientations and positions.

Assessment Standard 3.4: We know this when the learner designs and uses nets to make models of geometric solids studied up to and including this grade;

Assessment Standard 3.7: We know this when the learner draws and interprets sketches of solids from different perspectives.

Questions & Answers

anyone know any internet site where one can find nanotechnology papers?
Damian Reply
research.net
kanaga
Introduction about quantum dots in nanotechnology
Praveena Reply
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
Bharti
do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
Damian Reply
absolutely yes
Daniel
how to know photocatalytic properties of tio2 nanoparticles...what to do now
Akash Reply
it is a goid question and i want to know the answer as well
Maciej
characteristics of micro business
Abigail
for teaching engĺish at school how nano technology help us
Anassong
Do somebody tell me a best nano engineering book for beginners?
s. Reply
there is no specific books for beginners but there is book called principle of nanotechnology
NANO
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
s.
fullerene is a bucky ball aka Carbon 60 molecule. It was name by the architect Fuller. He design the geodesic dome. it resembles a soccer ball.
Tarell
what is the actual application of fullerenes nowadays?
Damian
That is a great question Damian. best way to answer that question is to Google it. there are hundreds of applications for buck minister fullerenes, from medical to aerospace. you can also find plenty of research papers that will give you great detail on the potential applications of fullerenes.
Tarell
what is the Synthesis, properties,and applications of carbon nano chemistry
Abhijith Reply
Mostly, they use nano carbon for electronics and for materials to be strengthened.
Virgil
is Bucky paper clear?
CYNTHIA
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
NANO
so some one know about replacing silicon atom with phosphorous in semiconductors device?
s. Reply
Yeah, it is a pain to say the least. You basically have to heat the substarte up to around 1000 degrees celcius then pass phosphene gas over top of it, which is explosive and toxic by the way, under very low pressure.
Harper
Do you know which machine is used to that process?
s.
how to fabricate graphene ink ?
SUYASH Reply
for screen printed electrodes ?
SUYASH
What is lattice structure?
s. Reply
of graphene you mean?
Ebrahim
or in general
Ebrahim
in general
s.
Graphene has a hexagonal structure
tahir
On having this app for quite a bit time, Haven't realised there's a chat room in it.
Cied
what is biological synthesis of nanoparticles
Sanket Reply
what's the easiest and fastest way to the synthesize AgNP?
Damian Reply
China
Cied
types of nano material
abeetha Reply
I start with an easy one. carbon nanotubes woven into a long filament like a string
Porter
many many of nanotubes
Porter
what is the k.e before it land
Yasmin
what is the function of carbon nanotubes?
Cesar
I'm interested in nanotube
Uday
what is nanomaterials​ and their applications of sensors.
Ramkumar Reply
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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Source:  OpenStax, Mathematics grade 7. OpenStax CNX. Sep 16, 2009 Download for free at http://cnx.org/content/col11075/1.1
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