2º ESO

HOW TECHNOLOGY AFFECTS TO THE ENVIRONMENT?

There are so many ways Technology affects in our world, between them we can find :

• Atmospheric Pollution ⇙

• Water Pollution ⇙

• Soil Pollution ⇙

Now we are going to watch a "funny" but truly video about pollution on Earth.

CLIMATE CHANGE

Many studies demostrate that the increase of greenhouse gases are causing a global temperature increase...

 WHAT THAT MEANS?

• Gradual disappearance of the polar ice caps
• Increased sea level

SOLUTIONS

• The awareness of citiziens and encourage them to use resources in a reasonable way.
• The three "R"s : REDUCING, RECYCLING,REUSING

THE PROCESS OF SOLVING TECHNOLOGICAL PROBLEMS

MATERIALS AND RAW MATERIALS

Mainly the two different kinds of materials are:

• RAW MATERIALS: which come from nature, plants, animals or rocks.
• MANUFACTURED/MAN MADE: which are obtained from natural materials through chemical processes.

Let´s going to see some examples:

COTTON: it is a raw or natural material but we process into clothing.

LEATHER: it is a natural material and we change it into a leather jacket.

CLAY: comes directly from the earth and we process it and we get a clay jar.

SAND: we find it in nature and when we manufactured it becomes a glass.

ACTIVITIES

1.Here is a list of material. Could you say which one is natural?

 1. Wood                 6. Leather             11. Nylon
  2. Paper                7. Oil                   12. Rayon

   3. Chalk                 8. Gold                 13. Cotton
4. Glass                 9. Coal                 14. Sand
5. Silk                 10. Plastic             15. Tin

2. Play Kahoot.

Raw materials and manufactured

3. Listening: fill the gaps below.

What has happened to America's honeybees?

Last fall, .......................... from states with warm climates began to report a sudden loss of honey bees. Losses were reported in twenty-four states and into Canada. Today, some beekeepers say thirty percent to ninety percent of their honeybees are gone. Food prices could.............................as a result. 

And some beekeeping businesses have failed. 

Many kinds of plants, trees, and grasses need bees to pollinate them. Bees gather ............................. from flowers during this process. The liquid gives them food and material to make honey. As the bees land on flowers, their bodies ................................ and ......................... fine particles of ....................... . 

Most flowering plants need pollination to reproduce. 

Honey bees can die during the winter. But few dead bees have been found. Instead, the bees seem to have disappeared. Experts call the condition "colony collapse................ ."

Agriculture Department official Caird Rexroad said the collapse threatens about fifteen billion dollars worth of the country's farm economy. Mister Rexroad commented at a hearing of a House of Representatives agriculture subcommittee.

Mister Rexroad said the cause of the sudden .......... of bees is not clear. The number of honey bees already had fallen before the colony collapse disorder began. 

Experts say the varroa mite is at least partly responsible for the earlier decrease in honeybees. The mite is a tiny .........that feeds on honeybees.

It may play a part in colony collapse disorder by carrying bee ............ .

Or the problem may be caused by other diseases and weather conditions.

A group of scientists is examining bees from more than one hundred colonies across the country.

The researchers also are studying the pollen, honey, and ........ that the bees produce. They are working with the Agriculture Department's Agricultural Research Service.

Diana Cox-Foster of Pennsylvania State University is part of the scientific group.

Miz Cox-Foster says the nation needs honeybees that can ....... themselves better against disease and insects.

The recent mapping of most of the honeybee's ......... offers hope of a stronger honeybee some day.

• PROPERTIES OF MATERIALS

1. MECHANICAL PROPERTIES:

HARDNESS: resistance of a body to being pierced or scratched by another body. 

Diamond

MECHANICAL RESISTANCE: the ability of a body to resist forces applied to it without breaking or changing shape.

Steel´s chain

TOUGHNESS: A body´s resistance to being changed, deformed or broken. 

Iron

BRITTLENESS:The ability to break easily, without being hardly deformed at all.

Lightbulb

ELASTICITY: the ability of a material to return to its original shape after being deformed.

Elastic spring

PLASTICITY: the ability of a body to become permanently deformed without breaking.

Mud or clay

2. THERMAL PROPERTIES:

EXPANSION: the increase in size of a body when its temperature rises.

Expansion joint

THERMAL CONDUCTIVITY: the ability to transmit heat.

Metals: such as iron, bronze, copper, gold, silver.

3. ENVIRONMENTAL PROPERTIES:

TOXICITY: how strong a poison or toxin is.

Batteries, detergent, bleach, chlorine, paints.

ENVIRONMENTAL HAZARD: the level of toxic effect a contaminant has on a ecosystem.

PVC

RECYCLABILITY: the possibility of reusing a material.

Cork, plastic buttons, paper, paperboard

BIODEGRADABILITY: a material´s ability to naturally decompose.

WOOD AND ITS PROPERTIES

Wood is an organic material that trees are made of. We use in many objects (such as tables, chairs, doors...)

Wood comes from trees and men transform it to obtain the material used to make different products.

If we cut a tree trunk in the middle, we would see

Now we are going to watch a video about timber process

WOOD PROPERTIES 

HYGROSCOPICITY

FLEXIBILITY

HARDNESS

SPLITABILITY

THERMAL AND ELECTRICAL INSULATION

TOUGHNESS

SOUND CONDUCTIVITY

Listening: Wood

Deforestation

FORCES AND STRUCTURES

Let´s listen to this song and try to complete the song with the words given:

STABILITY SONG

CONTROL, PRESERVATION, GLORY, STICK, STORY, BALL

The______ is so round 

And everyone wants a goal 

First thing is the _______ 

Then you use your instep for sure 

There are so many sides to a story 

Only three sides to a coin 

In life ________with Jah Jah glory 

The ____________of your life 

That’s your integrity, yeah

 There are so many side to a _______ 

Only three sides to a coin

 In life stick with Jah Jah _________ 

The preservation of your life 

That’s your integrity, yeah

NOW WE ARE GOING TO DO A PROJECT ABOUT STRUCTURES WITH PAPER ROLLS OR STRAWS

SIMPLE MACHINES

La palanca (vídeo explicativo)

TIPOS DE PALANCAS- (desde minuto 1:03)