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Technology

Grade 5

Machines made easy

Module 2

Levers

Let’s look at levers

One of the easiest ways to lift a heavy object is by using a lever.

Assignment

  1. What is a lever?

A lever is a beam that rests on something or that is attached to something and it works on this point of support or fulcrum.

  1. How does a lever work?

By applying a force a heavy load can be moved relatively easily.

  1. We get three main types of levers, namely:

Type1: A lever where the fulcrum is between the load and the force, e.g. a balancing scale.

Type 2: A lever where the load is between the force and the fulcrum, e.g. a wheelbarrow.

Type 3:

A lever where the force is between the load and the fulcrum, e.g. a man who is fishing.

  1. INVESTIGATION.

Do the following experiments on the type 1 lever in groups.

  1. What materials do you need?

a long metal woodwork ruler;

a small block of wood / eraser / round container

a medium-sized coffee tin with a lid / a pill container

drawing pins / paper clips

Experiment 1

  • Aim:

To determine how a lever works.

  • Method:

Make a lever by placing the metal rule on the block of wood.

Place the block of wood under the 15 cm mark on the ruler.

Fill the tin halfway with sand.

Place the tin of sand on the 0 cm mark on the ruler.

Now press on the ruler at the 30 cm mark.

Fill the tin completely with sand.

Press on the ruler at the 30 cm mark again.

Lift the empty tin and note how heavy it is.

  • Observation :

Is the half filled container lifted?

Is the full container lifted?

  • Conclusion :

Was it just as difficult as when you tried to lift the tin by yourself?

Assignment

Make a sketch with labels of experiment 1.

[LO 1.12]

  1. Experiment 2
  1. Aim :

To determine what will happen if we move the fulcrum.

  1. Method :
  1. Place the block of wood under the 20 cm mark on the ruler.

Place the half-filled container with drawing pins on the 0 cm mark on the ruler.

Now press on the ruler at the 30 cm mark.

OR

  1. Place the block of wood under the 10 cm mark on the ruler.

Place the filled container with drawing pins on the 0 cm mark on the ruler.

Now press on the ruler at the 30 cm mark.

  1. Observation :

Choose the correct word in brackets:

It is easiest to lift the container with drawing pins when the fulcrum is ( closest to/furthest away from ) the container with drawing pins. The experiment that proves this is attempt 2 (X / Y).

In attempt 2 (X / Y) the distance that you have to press down is the shortest.

  1. Conclusion :

The further away the pressure is from the (pivot / fulcrum), the greater is the pushing force exercised on the container, therefore making it easier to lift.

  1. Experiment 3
  1. Aim :

To determine where to push on a lever to obtain the best result.

What materials do you need?

A ruler.

A pencil.

2c coins.

  1. Method :

Place the pencil under the ruler in the middle. Place a coin at the one end of the ruler.

Let the other coin fall from a height of 30 cm to hit the ruler in the middle between the fulcrum and the other end.

  1. Observation :

Complete the illustration by drawing your observation.

Repeat steps 1 and 2 of the method, but let the coins fall on the edge of the ruler.

  • Observation : The coin shoots (higher/lower) if the coin falls on the edge.
  • Conclusion : The further away the pressure from the fulcrum, the greater the pushing force.
  • Self-assessment

How did my group do in the experiments?

Write down the names of the learners in the group.

Write “yes” or “know” next to numbers 1 to 8.

My group followed the instructions.
My group worked as a team.
We enjoyed the experiments.
We did well.
We helped and supported one another if something was not clear.
I listened to the other group members.
We all did the same amount of work.
I enjoyed working with my group.

9. If your answer to 7 is no , answer the following questions:

  1. Who did the most? Why?
  2. Who did the least? Why?
  3. Discuss your answers in your group. Have you learned anything from this assignment? If so, write down what you have learned.

[LO 1.3]

Assessment

LO 1

TECHNOLOGICAL PROCESSES AND SKILLS

The learner will be able to apply technological processes and skills ethically and responsibly, using appropriate information and communication technologies.

We know this when the learner:

Investigates:

1.2 finds out about existing products relevant to a problem, need or opportunity, and identifies some design aspects (e.g. who it is for, what it looks like, what it is for, what it is made of);

  • performs, where appropriate, scientific investigations about concepts relevant to a problem, need or opportunity using science process skills:

1.3.1 planning investigations;

  • conducting investigations;

1.3.3 processing and interpreting data;

1.3.4 evaluating and communicating findings.

Makes:

1.7 outlines a plan that shows the steps for making, including drawings or sketches of main parts;

1.8 uses suitable tools and materials to make products by measuring out, cutting or separating, shaping or forming, joining or combining, and finishing the chosen material;

Evaluates:

1.10 evaluates, with assistance, the product according to the design brief and given specifications and constraints (e.g. people, purpose, environment), and suggests improvements and modifications if necessary;

1.11 evaluates the plan of action followed and suggests improvements and modifications if necessary;

Communicates:

  • produces labelled two-dimensional drawings enhanced with colour where appropriate.

LO 2

TECHNOLOGICAL KNOWLEDGE AND UNDERSTANDING

The learner will be able to understand and apply relevant technological knowledge ethically and responsibly.

We know this when the learner:

Systems and control:

  • demonstrates knowledge and understanding of how to use energy sources to power mechanical systems in order to make a product move in some way.

Questions & Answers

Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
Renato
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
?
Kyle
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
Adin
why?
Adin
what school?
Kyle
biomolecules are e building blocks of every organics and inorganic materials.
Joe
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
research.net
kanaga
sciencedirect big data base
Ernesto
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
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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Source:  OpenStax, Technology grade 5. OpenStax CNX. Sep 23, 2009 Download for free at http://cnx.org/content/col10979/1.2
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