Posted on October 14th, 2009 by Technology Department
A Bit about Temperature and heat.
Heat always travels from a warmer area to a cooler one. In a fridge, there is a heat-exchanging tube ( Evaporator ) that absorb heat from the hoot food and it is leaves because another heat-exchanging tube ( Condenser ) outside the refrigerator.
In Spain, Temperature is measured in degrees Celsius (°C). In USA and UK is measured in degrees Farenheit (°F). For example, in case of water:
Ice melts at 0°C.
Water boils at 100°C
Now, watch the next video and pay attention.
1º Click on video 1
2º Click on video 2
3º Click on video 3
Activity: Copy in your notebook the questions of every video. Replay all the question after watching the videos
Exercises 1: Use as many words as you need to describe the following materials:
Properties: Strong, light, weak, heavy, low density, translucent, electrical conductor, magnetic
a) Wood b) Plastic c) Fabric d) Iron e ) Glass f ) Cork g) wool h) Aluminium
Exercise 2: Copy into your notebook the properties of transparent, opaque, waterproof, hard, strong and conductor.
Rocks and soils
Rocks can be permeable or impermeable hard or soft, or even can
splits easily into thin sheets such as the Slate. We are going to learn
some aspect about granite, marble, chalk and slate.
Soils are a combination of very small particles of rock, dead animals and plants plus air and water.
4º Click on video 4
Exercises 3. Test Only read and Think.
1.Which of the following rocks is permeable?
2.Which rock splits easily into thin sheets?
3.Which is the only rock that floats?
4. What would be a good rock to tile a roof with?
5. Granite is often used for steps because ...
A. it doesn't wear away easily
B. it is very nice
C. it doesn't float
D. it's permeable
6. Chalk is used to write on blackboards because ...
A. it doesn't float
B. it wears away easily
C. it's permeable
7.Marble is often used for statues or grand buildings because ...
A. It has attractive textures and colours
B. It splits easily into thin sheets
C. It is waterproof
D. It wears away easily
Conductors and Insulators. Try not to blow anything up!
5º Click on video 5
Exercise 4: Test
1. An electrical conductor is
A. A material that lets electricity pass through it
B. A material that does NOT let electricity pass through it.
C. A raw material
D. A material that lets heat pass through it
2. Which of the following materials is an electrical insulator?
D. Wet paper
3. Why is electrical wiring usually covered with a layer of plastic?
A. To make it look very pretty
B. To protect against water
C. To help electricity flow quickly along the wire
D. To make it safe for people
4. A electrical wiring is usually made from ...
5. Mary makes a simple circuit with one bulb and three 1,5 volts batteries. The bulb lights for 2 seconds and then blow up. Why?
A. Too much electrons flows through the filament
B. The batteries are all flat
C. Not enough electricity flows through the circuit
D. The bulb's filament is not hot enough
Cork: The elastic outer bark of the holm oak, used especially for insulation, bottle closures, etc.
On the left, a holm oak, a typical tree in Extremadura
Pumice: A light, porous, glassy lava rock.
Chalk: Soft compact calcite, CaCO3, with other elements such as quartz, feldspar, etc