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Natural sciences

Grade 9

Energy: forces and machines

Module 21

Work and conversion of energy

Activity 1:

Describing the relationship between effort and energy with reference to a turbine

[LO 1.2, 2.1, 3.2]

Energy is necessary for any performance of work. This energy must be obtained from FUELS or from CONVERTED forms.

CONSTRUCTING A SIMPLE TURBINE

  • Use a tin lid, cut it into segments to form it into a fan and make a hole in the centre.
  • Nail the fan to a piece of wood.
  • Boil water in a kettle, until there is a strong draught of steam.
  • Hold the fan in position so that the jet of steam will be directed towards its centre.
  • QUESTIONS

1. What happened?

2. What kind of energy conversion occurred?

3. Describe the form of energy conversion that occurs with wind towers such as those that have recently been erected along the West Coast in the vicinity of Malmesbury.

4. What advantages do wind towers like these have for the environment?

  • Write a paragraph (60 words) about the value that the principle of the turbine has for people.
  • WORK is also measured in (give the name of the unit) .…………....................................

Activity 2

Discussing other machines that operate by means of conversion of energy

THE MICROSCOPE

  • As long ago as the early 17 th century, Robert Hook assumed that light rays have energy and that a wound-up spring has potential energy. He also constructed the first microscope and was the first person to use the universal lever, which is used in a wide range of instruments and cars.

SATELLITES

  • Satellites depend on solar panels to absorb light energy from the sun and supply electricity for all other electronic functions and for cameras and radio equipment. Energy is also stored in chemical form in rechargeable batteries.

WIND PUMPS

  • The blades of the rotary disk are turned by the wind to drive a pump that pumps underground water to a storage dam.

Assignment 3: GROUP DISCUSSION

  • Name at least three other machines that operate by means of energy conversion and explain the workings of each one.

WHEN IS A MACHINE MECHANICALLY INEFFECTIVE?

  • When a machine or appliance fails to provide an adequate quantity of the energy that it has been designed to provide we say that it is in affective.
  • The light bulb, for instance, releases (unwanted) heat, but was actually designed to provide light!
  • In this instance, fluorescent lighting is more effective and economical.
  • Are you able to list further examples?

Assessment

LO 2
Scientific KnowledgeThe learner will know and be able to interpret and apply scientific, technological and environmental knowledge.
This is displayed when the learner:
2.1 is able to recall meaningful information;
2.2 is able to arrange information according to categories;
2.3 is able to interpret information;
2.4 is able to apply knowledge.
LO 3
Science, Environment and the CommunityThe learner will be able to demonstrate an understanding of the interrelationships between science and technology, society and the environment.
This is displayed when the learner:
3.1 is able to show appreciation of science as a human endeavour;
3.2 is able to recognise the value of sustainable utilisation of resources.

Memorandum

Activity 1

Questions:

1. The fan (‘turbine’) rotates

2. Chemical to steam to kinetic / mechanical

3. Kinetic to electrical to chemical

4. Natural resources (e.g. coal) are not used and pollution is avoided

Paragraph:

  • E.g. natural energy is converted to usable energy
  • Without consumption of resources
  • Without pollution
  • There are no waste products to be got rid of
  • Examples of utilising turbines: generation of electricity, previously also for driving mills

Effort is measured in Joule

Activity 2

  • Any power generator
  • Compressor
  • Vehicle engine
  • Sewing machine
  • Kitchen appliances
  • Etc.
  • Ineffective machines: any machine or system that releases energy in a non-usable form, e.g. a car that is driven with the hand break on (much energy is wasted in the attempt to overcome the force of friction – energy in the form of heat goes to waste).

Questions & Answers

are nano particles real
Missy Reply
yeah
Joseph
Hello, if I study Physics teacher in bachelor, can I study Nanotechnology in master?
Lale Reply
no can't
Lohitha
where we get a research paper on Nano chemistry....?
Maira Reply
nanopartical of organic/inorganic / physical chemistry , pdf / thesis / review
Ali
what are the products of Nano chemistry?
Maira Reply
There are lots of products of nano chemistry... Like nano coatings.....carbon fiber.. And lots of others..
learn
Even nanotechnology is pretty much all about chemistry... Its the chemistry on quantum or atomic level
learn
Google
da
no nanotechnology is also a part of physics and maths it requires angle formulas and some pressure regarding concepts
Bhagvanji
hey
Giriraj
Preparation and Applications of Nanomaterial for Drug Delivery
Hafiz Reply
revolt
da
Application of nanotechnology in medicine
has a lot of application modern world
Kamaluddeen
yes
narayan
what is variations in raman spectra for nanomaterials
Jyoti Reply
ya I also want to know the raman spectra
Bhagvanji
I only see partial conversation and what's the question here!
Crow Reply
what about nanotechnology for water purification
RAW Reply
please someone correct me if I'm wrong but I think one can use nanoparticles, specially silver nanoparticles for water treatment.
Damian
yes that's correct
Professor
I think
Professor
Nasa has use it in the 60's, copper as water purification in the moon travel.
Alexandre
nanocopper obvius
Alexandre
what is the stm
Brian Reply
is there industrial application of fullrenes. What is the method to prepare fullrene on large scale.?
Rafiq
industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
Damian
How we are making nano material?
LITNING Reply
what is a peer
LITNING Reply
What is meant by 'nano scale'?
LITNING Reply
What is STMs full form?
LITNING
scanning tunneling microscope
Sahil
how nano science is used for hydrophobicity
Santosh
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
Rafiq
what is differents between GO and RGO?
Mahi
what is simplest way to understand the applications of nano robots used to detect the cancer affected cell of human body.? How this robot is carried to required site of body cell.? what will be the carrier material and how can be detected that correct delivery of drug is done Rafiq
Rafiq
if virus is killing to make ARTIFICIAL DNA OF GRAPHENE FOR KILLED THE VIRUS .THIS IS OUR ASSUMPTION
Anam
analytical skills graphene is prepared to kill any type viruses .
Anam
Any one who tell me about Preparation and application of Nanomaterial for drug Delivery
Hafiz
what is Nano technology ?
Bob Reply
write examples of Nano molecule?
Bob
The nanotechnology is as new science, to scale nanometric
brayan
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Damian
Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
Renato
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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Source:  OpenStax, Natural sciences grade 9. OpenStax CNX. Sep 15, 2009 Download for free at http://cnx.org/content/col11069/1.1
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