Iron core Coil of insulated wire surrounds the iron core. Electrical output rd wei or what? Lodestone is a naturally occurring magnet thought to be made when lightning strikes. The insulated wire stops the current from taking a shortcut from loop to loop and keeps it flowing around the core. Power plants There are two kinds of energy— renewable and nonrenewable.
Earth will run out of nonrenewable fuels, but renewable energy comes from endless resources such as wind and sun. In Shanghai, China, vast quantities of coal are loaded on a conveyor belt. Burn, burn, burn Most power plants burn nonrenewable fossil fuels like coal, oil, and natural gas. These are formed from fossilized plankton or plants that lived millions of years ago.
Smoke and hot gases escape from the chimney. Heat from burning coal turns water in the pipe into steam. Ash collects underneath.
The steam drives the turbine. Flow of steam The turbines produce electricity by turning a magnet inside a large coil of wire. Cooling water out Pump The steam passes into a condenser. Crushed coal and hot air Pump brings in cooling water. Ash As the steam condenses to water, it collects in this tank. Flow of water 62 How far does power travel? Cold water in the pipe cools the steam so it condenses. Power plants Dangerous power Nuclear power plants create energy by splitting uranium atoms, which release heat to run the generators that make electricity.
Nuclear power is nonrenewable because there is a limited supply of nuclear fuels. The waste from these fuels is radioactive, so they may damage cells and cause cancer.
On April 26, , at a. Over 20 years later, an inspector checks the interior left. Solar power comes from the Sun. In theory, it could provide all our energy. Hydroelectric power is created by falling water, like a dam or waterfall.
Wind power is generated by turbines. Lots of them together make a wind farm. Tidal power uses water in the form of waves rather than waterfalls. Stretched between towers, cables carry high currents. Power masts are huge steel towers. They have extra wires running along the top to ground lightning. Substations reduce voltage and send power in different directions. On the way All over the world, rows of masts march across the landscape.
They support the high-tension cables that carry electricity from power plants to homes and offices. Electricity is wired to power points in your home. It connects with equipment through a plug.
Local grid Cables below ground 63 Power can travel up to miles km to your home. Running out What can you do to save energy? Most of the energy we use comes from burning fossil fuels. Turbines in a coal-fired power plant without their metal covers. Steam power Electricity that comes from coal is relatively inexpensive to make. In a machine called a pulverizer, the coal is broken down into a fine powder, then burned in a furnace.
The furnace heats a boiler to produce steam. The steam powers turbines that run generators to create electricity. Tall pipes are used to drill oil from the ocean floor. Oil and gas We get oil by drilling under the ground— from dry land, or from the ocean floor. Today, we use oil for 38 percent of our energy, either as fuel for heating, or turned into gasoline for cars and planes.
Experts think oil reserves will run out in about 40 years. Try to eat food that is produced locally. Ask your parents to make sure your home is insulated. Save gasoline. When you can, walk instead of asking for a ride. Turn off your television and computer. Switch off lights when you leave a room, and use energy-saving light bulbs. Dry laundry outside instead of using a dryer. Recycle and reuse items such as glass, plastic, and paper.
Oil rig Oil reservoir Marine life that has decayed. How much oil can the largest oil rig store? A layer of rock traps the decaying remains, which turn into oil. Running out rd i e w Compressed lignite turns into coal. Compressed peat becomes lignite. Decaying plants form peat.
Peat is the earliest stage in the formation of coal. Underground gas Natural gas is also a fossil fuel. It comes from coal beds, marshes, bogs, and oil reserves. Natural gas is likely to run out in about years. At the moment, it provides 23 percent of our energy.
In the US, about half of all the electricity used comes from coal-burning power plants. Black diamonds Like diamonds, coal is a form of carbon. Gas facts Easily piped into homes, natural gas is completely clear and odorless.
When it burns, it releases lots of energy, which makes it suitable for use in cooking, heating, and cooling.
Renewable energy Energy made from fossil fuels will eventually run out, but certain types of energy are renewable, which means that we can go on using them forever. High-speed shaft un Blade eh Wind farms are where lots of turbines are installed in a field or in the sea. Generator On Brake no it o Substations divide power so it can travel in different directions. The transformer sends alternating currents into power lines.
Wind power Wind turbines use the power of moving air currents to spin their propellers. These are huge windmill-like blades on top of a tall tower. As they spin, generators inside the turbines make electricity, which is sent via cables underground. The electricity travels underground to a transformer station. When was the first geothermal plant built? Taller towers generate more electricity. Underground Renewable energy The spillway of a dam is used to control the flow of water.
Water from a reservoir flows down a pipe to a turbine. Usually a dam is built to trap a river and create a lake. Water is released at a controlled rate and allowed to flow through a spinning machine called a turbine, which drives an electricity generator. Solar energy Huge glass panels are put on the roofs of buildings to capture energy from the Sun and convert it into electricity.
The stronger the sunlight, the more electricity they make. Geothermal energy uses the heat from these rocks to generate electricity and heat water. When sunlight lands on a cell, electrons are pushed from one layer to the other creating an electric current.
Each cell contains silicon doped made impure with phosphorus, which produces free electrons. One of the biggest geothermal areas in the world is Iceland.
People can swim next door to this geothermal plant in Iceland since the water is so warm. Biofuels Biofuels come from fast-growing crops, such as corn, sugar cane, and palm oil. These fuels can add to or replace fossil fuels such as diesel or gas. Biofuels have been criticized for taking up land that could be used to grow food. The stove is probably the most important piece of equipment in the kitchen. The oven Heat is a form of energy.
It comes from the movement of atoms and molecules. The faster the molecules move around, the higher the temperature. Inside an electric oven are large coils of wire called heating elements. These heat up when electricity travels through them. They are controlled by a thermostat that keeps the temperature inside constant. On a burner, the element is in direct contact with the saucepan, which passes the heat through to the food.
Dial controlling the thermostat. Because the broiler element is much closer to the food and gets hotter than the one in the oven, the food cooks quickly. Convection ovens have fans that blow air around and keep the whole oven at the same temperature.
Food cooks faster in a convection oven. The oven works by surrounding the food with hot air. Since hot air rises, the top of the oven is slightly hotter than the bottom. When the oven gets too hot, the thermostat turns the heating elements off. It turns them back on again when the oven cools. Cooking is simply delicious experiments in chemistry and physics. Cooking eggs Egg whites and yolks are made of stringy chains of protein floating in water. Chains of protein Each individual chain is twisted and curled up.
When you add heat, the chains uncurl and start to link together. Chains of protein unravel and join up. Baking bread A basic bread mixture includes flour, water, and yeast.
Yeast is a live, single-celled fungus. Flour, when it mixes with water, releases stretchy gluten. When the bread mix is left in a warm place, the yeast starts feeding on the sugars in flour and releases carbon dioxide gas. As you cook it, the water boils away, leaving a much stronger solution of sugar.
Very strong solutions make toffee or hard tack candy. Water boils out of the sugar. Gas is released. The chains form a mesh that traps the water they floated in. The egg is now cooked. The gumlike gluten fills with thousands of gas bubbles and the bread rises. Cooking traps the bubbles in the bread.
If you stir the mixture as it cools, it forms crystals. This is how you make fudge, but you leave hard candy to set without stirring. The chains form a mesh. Electricity makes all this possible. Let cheese warm up before you eat it. Eggs are usually stored in the refrigerator door, which is a few degrees warmer than the shelves. Room temperature Dry foods such as beans and pasta keep very well at room temperature.
Refrigerator The temperature inside a refrigerator is cold enough to slow down the growth of bacteria germs in our food, so it stays fresh longer. Dairy products, meat, and fish should always be stored here.
Freezer Freezers are cold enough to make your skin freeze! Most foods are thawed or warmed before you eat them. Lettuce and other salad vegetables go in the door, or in a drawer at the bottom of the refrigerator. Cool coil A long coiled pipe is set into the refrigerator walls. Inside is a gas called tetrafluoroethane, which travels around the fridge soaking up heat. This heat travels to a compressor, and is then released at the Gas coolant back, which is why it feels circulating around fridge warm there.
How quickly do bacteria grow at room temperature? Keeping cool Adjustable temperature control Warmed coolant Compressor Control electronics Compressor 71 In just four hours, one bacterium can turn into more than 1,! Energy efficiency Every home needs energy for heating, lighting, cooking, and lots of other things. Eco living Triple-paned windows have three panes of glass with a layer of air between them.
The air stops heat from escaping, so you need less energy to heat the house. The windcatcher channels air into the house, providing ventilation. The aluminum tubing reflects light inside. Sustainable homes are designed to be better for the environment. They have lots of features that save energy and water. They produce fewer carbon emissions and are also cheaper to run. The outside of the roof is covered in photo-voltaic and solar panels.
These generate electricity for the whole house. A biomass boiler burns wood pellets for heating and hot water during the winter. What are carbon emissions? Energy efficiency Batteries In your home We can all do things to make our homes more energy efficient. A lot of energy is used to heat a house.
Ask your parents to lag your attic with insulation to keep heat in. You can also insulate walls and floors, plug gaps around doors and windows, and install double-paned windows. Thermograms are pictures that show hot things as white and yellow and cold things as blue. The hottest part of this house is its windows, because heat is escaping through them. When rain hits the roof, it collects in a gutter and runs down a pipe into a recycling tank.
The water is used in a washing machine. Every household uses batteries to power all kinds of things—but batteries eventually run out. So how should you dispose of them? Change old batteries right away.
Batteries contain chemicals that may leak and ruin the gadget. Insulating a loft Become an expert Batteries should never be thrown onto a fire— they might explode. But some items are simply too dangerous to throw away. Old refrigerators contain gases that are harmful if they leak. The safest way to get rid of a broken refrigerator is to contact your local recycling center. Go online to find charities, schools, and groups that can make good use of your unwanted equipment. Light and sound Light and sound of What is light?
Light is a type of energy called electromagnetic radiation, or EMR. Atoms—the tiny particles that make up everything around us— are that source. Atoms that have too much energy can get rid of it in the form of light. Light travels in straight lines, but it can change direction. When light passes through a prism usually a threedimensional glass triangle , it bounces off the sides of the prism and bends.
Some colors in light bend more than others, so they spread out and you can see the different colors. Th e S A glass prism splits the light into colors. Most of what we know about the world we learn by seeing and hearing. Everything we see needs light, and everything we hear involves sound.
They can both reach us by traveling in waves. Light travels faster than anything else in the universe— an amazing , miles per second , km per second! It takes just eight minutes for light from the Sun to reach Earth. Secrets of sound Light and sound Curiosity quiz When something vibrates, it squeezes and stretches the air around it, sending out waves that we hear as sound.
Echolocation Some animals use sound to find their way around. This is called echolocation. Bats send out high-pitched squeaks that bounce off their surroundings.
Cymbals make large waves, which means a loud sound! The speed of sound Sound travels more slowly than light, at 1, ft per second meters per second in air. But the speed changes, depending on what the waves are traveling through.
They can move four times faster in water than in air. Light and sound Now you see it… Light waves or electromagnetic waves are all different lengths, but each length travels at the same speed. Some light waves are too short or too long for us to see. Blue Cyan Green Red We use invisible electromagnetic waves in our lives every day. Radio waves Radio waves carry sound and images through the air.
Radios, televisions, and cell phones all use radio waves. The longest radio waves can be , times longer than the shortest ones. Each length appears as a separate color. For example, red waves are long and blue rays are short. Light contains an endless amount of colors.
The only limit is on how well your eye and brain can tell one wavelength from another. Microwaves Microwaves heat water molecules in food and liquid, but they pass straight through glass and plastic. What is white light? Infrared waves Infrared waves carry heat. We can see infrared waves with night-vision goggles or special cameras, both of which are designed to pick up heat rather than light. Prisms and rainbows Light bends when it passes through a prism.
Each color bends at a different angle, so they separate out and form a rainbow. Each drop of water, depending on where it is, bounces a particular color into your eyes. You see these colors as the bands in a rainbow. Visible Everything we see can be seen because visible light waves bounce off objects. Light waves can come from the Sun and from light bulbs.
Ultraviolet UV rays Ultraviolet waves come straight from the Sun. Some UV waves can burn your skin and, over time, cause wrinkles and cancer. A well-cut diamond is the best prism there is. Because it has so many different surfaces, light bounces around inside, creating bright, sparkly colors.
X-rays X-ray waves pass through most things, but not bones, teeth, or metal. When doctors want to look at your bones, they take X-ray pictures to see if anything is out of place or broken. Gamma rays Gamma rays can bore through solid objects and kill living cells. Doctors use them in radiation treatments to destroy cancer cells.
Gamma rays are also released when nuclear bombs explode. All the colors of visible light appearing together. Visible spectrum Now you see it Bubble colors There are different colors in a bubble purple, yellow, and blue from those in a rainbow green, blue, and red.
This is because a rainbow splits white light into separate colors, but a bubble subtracts colors from light. If red is subtracted, you see the greeny-blue that is left behind. Hands On Make your own bubble solution by mixing half a cup of dishwashing liquid with four cups of water and four tablespoons of glycerine.
Color secrets You can tell how thick a bubble is by the colors it reflects. The blue parts of bubbles are thickest and the black parts are thinnest. Bubbles start to turn black when they are about to burst. What happens when you blow soap bubbles in cold weather? Light and bubbles Tiny planets The patterns on a bubble look a little like the patterns of clouds around a planet.
Both are thin films of fluid, so they act in a similar way. This is why some scientists use bubbles as model planets—they study the surface patterns to discover how storms and hurricanes develop.
The colors on the surface of a soap bubble appear to swirl around like a storm on a planet. A storm has been raging on the planet Jupiter for years. Bubble shapes The water molecules in bubble solution hold tightly onto each other, constantly pulling together. This means that bubbles always take up the smallest surface area possible. When soap solution is stretched across a bubble wand, the smallest surface it can form is a flat plane.
If two bubbles meet in midair, they shrink their surface area by forming a shared, flat wall between them. When the solution is stretched around a pocket of air, the smallest surface it can make is a ball. When three bubbles meet, they share three walls. Full-color illustrations. Nonfiction Science Reference Childrens More details.
David Macaulay 55 books followers. David Macaulay, born in , was eleven when his parents moved from England to Bloomfield, New Jersey.
He found himself having to adjust from an idyllic English childhood to life in a fast paced American city. After working as an interior designer, a junior high school teacher, and a teacher at RISD, Macaulay began to experiment with creating books. He published his first book, Cathedral, in Following in this tradition, Macaulay created other books—including City, Castle, Pyramid, Mill, Underground, Unbuilding, and Mosque—that have provided the explanations of the how and the why in a way that is both accessible and entertaining.
Five of these titles have been made into popular PBS television programs. Search review text. This book taught me more about technology than my first five years of school, and that isn't intended as a criticism of the public educational system. I'm betting my dad got tired of the perpetual, "Why? Where else can a child be taught to understand the simple machines, fission, and how to pick a lock? E-Book Description. E-Book Details.
About the Authors. DK publishes highly visual, photographic nonfiction for adults and children. DK brings unrivalled clarity to a wide range of topics with a unique combination of words and pictures, put together to spectacular effect.
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These volumes are not a reference in the ordinary sense. Great for explaining concepts to children. In the Way Things Work, Macaulay depicts many machines and tools and gives explanations of how How Things Work book work and how to use them. It is separated into sections of movement, elements, light and sound waves, and electricity and automation. How Things Work - Kids: Books. So they can help their kids to grow healthy and happy.
View Product [ x ] close. Macaulay's explanations are lucid; they are also fun. He includes visual puns, running jokes, a cast of thousands of tiny participants in on and around the machines, choirs of angels and lots of big woolly mammoths.
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