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Powerppint slide for My year 10 class in Malone college. We where making a bottle holder for our project. In this lesson we where discussing theory on Types of woods and how levers work.
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Technology and DesignYear 10
Lesson 3
By the end of this lessons everyone will: Know what manufactured boards are Applications for Manufactured boards Know what a turning effect is Know examples of a turning effect Know what a lever is Know the 3 different classes of levers Know examples of levers
Learning Intentions
What are Manufactured
Boards???
Manufactured Boards (Man made wood)
1. MDF (medium density fibre
board)
2. Chipboard
3. Hardboard
4. Plywood
1. MDF (Medium Density Fibre board)What is MDF? MDF (medium density
fibre board) is made from fibres of wood mixed with glue.
They are made by heating the mixture and squeezing it between rollers and dried between to metal plates.
It is easy to work with and is used to make furniture
2. Chipboard
What is Chipboard? Chipboard is made from chips of wood (wood shavings).
It is easy to work with and is used to make kitchen units.
3. Hardboard
What is Hardboard? Hardboard is
another type which is made from very fine wood chips (a lot smaller than the chips used to make chipboard ) mixed with glue. It is smooth on one face and is rough on the other.
Hardboard is used to make the backs of cupboards.
4. PlywoodWhat is Plywood? Plywood is made by
gluing and compressing wood veneers tightly together.
A wood veneer is a thin slice of wood that was removed form a plank of timber by a specialised machine.
Plywood is a very strong piece of wood and it is used for flooring, wall partitions and packaging boxes.
Now, turn to page 9 in your work booklets and complete Worksheet 3
It is when two forces are opposing each other and the larger force overcomes the smaller force causing it to turn.
What is the Turning Effect?
Could you think of any examples
of a turning effect?
If these two forces were acting against each other who do you
think would win?
5N 12N
Yes, the rope would pull to the right as the adults have a greater force than the children which are pulling to the left.
Levers are one type of mechanism, some classes of levers can make the actions of an
applied force (called effort) easier to do with another class of levers the effort is harder to do
LeversWhat is a Lever?
COULD ANYONE GIVE ME AN EXAMPLE OF A LEVER??
Tweezers A wheel barrow A see saw A fishing rod A nutcracker A pair of scissors Using a spade Using a crowbar
These items all have levers:
Both class 1 and 2 levers are when the effort is smaller than the load. Examples are below:
There are three different classes of levers
Class 1 lever
Class 2 lever
A class 3 lever is different than the previous two, as it requires a bigger effort than the load. Examples are shown below.
Could anyone give me any other examples of
levers
Now, complete the lever
worksheet and finish for
homework
Tools we have used so far
Fretsaw Coping Saw Templates
Bench Vice Sand Paper Pillar drill
Wood can be joined together in many ways. Some are very simple to do but are weak e.g. the Butt Joint (shown below).