Summary#1*Energy Resources*

Many homes, shools, and business get heat by burning oil or natural gas. Some older buildings still burn coal for heat. Some homes burn wood for heat. The heat in many other homes and businesses comes from electricity. Many common devices, such as lights, computers, radios, TVs, and washers. Some small devices such as flashlights and portable CD players get their electricity from batteries. That electricity comes from a power planet. The power plant makes electricity by using energy from burning fuels such as coal, oil, and natural gas. It takes a lot of energy to move a car, bus, or train. Public an private transportation is one of the greatest uses of energy in today´s world. Heat from burning fossils fuels can bu used directly to heat homes, schools, businesses, and factories. The heat can also bu used to generate electricity. All fuels have advantages and disadvantages. The advantage of using fossil fuels is that they contain a lot of energy. However, fossil fuels take millions of years to form. Burning a fossil fuel also gives off smoke, gases, and other by-products. These pollute the envirotment. Fossil fuel are the remains of once-living things. Natural gaso or oil formed from the remains of tiny ocean plants and animals. These sea creatures died and fell to the bottom of the ocean. There their bodies were buried by layers of sand and mud. One day is to use alternative energy sources such as water, wind, and solar energy. Every watt of electricity we get from a solar cell is one less watt we have to get by burning oil or coal.

Vocabulary #16

Alternative Energy Source: a source of energy other than the burning of a fossil fuel.

Geothermal Energy: Earth´s internal energy.

Biomass: plant matter or animal waste that can be used as a source of energy.

Vocabulary #15

Desalination: getting fresh water from seawater.

Water Cycle: the continuous movement of water between Earth´s surface and the air,changing from liquid to gas to liquid.

Grounwater: water that seeps into the ground into spaces between bits of rock and soil.

Water Table: the top of the water-filled spaces in the ground.

Aquifer: an underground layer of rock or soil filled with water.

Spring: a place where groundwater seeps out of the ground.

Well: a hole dug below the water table that water seeps into.

Reservoir: a storage area for freshwater supplies.

Vocabulary #14

Renewable Resource: a resource that can be replaced in a short period of time.

Ozone Layer: a layer of ozone gas in the atmosphere that screens out much of the Sun´s UV rays.

Fossil Fuel: a fuel formed from the decay of ancient forms of life.

Smog: a mixture of smoke and fog.

Acid Rain: moisture that falls to Earth after being mixed with wastes from burned fossil fuels.

Vocabulary #13

Opaque: completely blocking light from passing through.

Transparent: letting all light through,so that objects on the other side can be seen clearly.

Translucent: letting only some light throught, so that objects on the other side appear blurry.

Polarization: allowing light vibrations to pass through in only one direction.

Refraction: the bending of light rays as the pass from one substance into another.

Convex Lens: a lens that curves outward (is thicker at the middle than at the edges) and brings light rays together.

Concave Lens: a lens that curves inward ( is thicker at the edges than at the middle) spreads light rays apart.

Vocabulary #12

Bioluminescence: light produced by living things.

Light Ray: a straight-line beam of light as it travels outward from its source.

Law of Reflection: the angle of an incoming light ray equals the angle of the reflected ray.

Concave Mirror: a mirror that curves in on the shiny side.

Convex Mirror: a mirror that curves out on the shiny side.

Vocabulary #11

Rock: a naturally formed solid in the crust,made up of one or more minerals.

Igneous Rock: a rock formed when melted rock material cools and hardens.

Sedimentary Rock: a rock made of bits of matter joined together.

Fossil: any remains or imprint of living things of the past.

Metamorphic Rock: a rock formed under heat and pressure from another kind of rock.

Humus: decayed plant or animal material in soil.

Pollution: adding any harmful substances to Earth´s land,water,or air.

 

Rock Cyccle: rocks changing from one form into anther in a never-ending  series of process.