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Grade 9


Module 4

How long is a piece of string?


1 Work in a group to answer the following questions:

1.1 How many metres is a thousand millimetres?

1.2 Which units are the best for giving the following quantities? Some are difficult, and you may have to do some research and bring a better answer back later.

1.2.1 How tall you are.

1.2.2 The distance between our sun and the nearest star.

1.2.3 How long it will take to walk from Cape Town to Cairo.

1.2.4 The amount of milk you drink in a year.

1.2.5 The quantity of vitamin C one has to take in daily.

1.2.6 The temperature of a patient in a hospital in New York.

1.2.7 The area of Greenland.

1.2.8 The speed of a car on the open road.

1.2.9 The amount of wood a cabinetmaker orders at one time.

1.2.10 The total amount of money the government collects in taxes in a year.



The passing of time.

  • We use watches and clocks to show how time passes.
  • Do the following questions as a project. Don’t make yourself guilty of plagiarism.

1 Explain the difference between analogue and digital clocks / watches.

2 List all the clocks in your home, and say whether each is analogue or digital.

3 Find at least one other method used to measure time or show the time – one that is not generally used in western culture. It can be something from earlier times, or something from another country. Try to find something about timekeeping in Africa. Explain clearly how it works.

  • The project must be handed in on: ..................................................

end of PROJECT


1 Complete any remaining questions from the class assignment above.

2 What measuring instruments are used for the following measurements?

2.1 How tall you are.

2.2 The mass of a new–born baby.

2.3 The amount of milk you have to add, in a recipe.

2.4 The paint used for painting the outside of an ordinary house.

2.5 Humidity.

2.6 The speed of a moving car.

2.7 We have a very complicated way of determining leap years. Find out:

2.7.1 Why we need to have leap years, and

2.7.2 Which years will be leap years.


Connecting with the world – ASSIGNMENT

  • Choose one of these questions to do.

1 You’ve just discovered your granny’s old recipe book. You remember some of her recipes, and you’d like to try them too. Unfortunately it uses old–fashioned units, which would be a lot of trouble to convert each time. Decide how you can make some kind of aid, like a table of graph or formula, to make conversions easier. The units that occur often are: the temperature of the oven is given in °F; the measures of mass are in ounces and pounds and the liquid measures are in pints.

2 Your father has just bought you a second–hand car, but it was imported from America and all the instruments use units you are unfamiliar with, and have difficulty making sense of. Decide how you can make some kind of aid, like a table or graph or formulae that you can understand exactly what units like miles, gallons, miles per gallon (petrol consumption) mean in our units.

Questions & Answers

Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
what school?
biomolecules are e building blocks of every organics and inorganic materials.
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
sciencedirect big data base
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.
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
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
characteristics of micro business
for teaching engĺish at school how nano technology help us
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
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
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.
what is the actual application of fullerenes nowadays?
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.
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.
is Bucky paper clear?
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
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.
Do you know which machine is used to that process?
how to fabricate graphene ink ?
for screen printed electrodes ?
What is lattice structure?
s. Reply
of graphene you mean?
or in general
in general
Graphene has a hexagonal structure
On having this app for quite a bit time, Haven't realised there's a chat room in it.
what is biological synthesis of nanoparticles
Sanket 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 9. OpenStax CNX. Sep 14, 2009 Download for free at http://cnx.org/content/col11056/1.1
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