Innholdsfortegnelse for November/December 2021 i Cobblestone American History and Current Events for Kids and Children

Electricity has become essential to modern life. It provides the power to do simple tasks from keeping on your bedroom light to the more complex job of keeping on an entire city’s lights. Perhaps the easiest way to understand electricity’s importance in our lives is to look around our homes. How many wall outlets do you see? Now, look at all the things that are plugged in. Electricity is the source of energy that powers: • our lights • our televisions and stereos • our cell phones and all the forms of communication they provide—phone calls, emails, texts, and social media • our computers and video games • our stoves, microwaves, refrigerators, dishwashers, blenders, and other kitchen appliances • our vacuum cleaners, washing machines, and clothes dryers • our ability to control our environment with fans, air…

Determining the answer to the above question sparked a feud between two of the greatest inventors of the 19th century’s Electrical Age. Thomas A. Edison and Nikola Tesla started out regarding each other with great respect. For a time, they worked together designing generators and other electrical devices for Edison’s electric company. But their friendship did not last. Edison favored direct current (DC). DC is simple to operate, but it can travel only in one direction and for short distances.DC power voltage also remains steady—it can’t be stepped up or down with transformers. Tesla developed a new system, called “polyphase alternating current” (AC). AC changes direction back and forth many times per second. AC is more complicated than DC, but it can travel greater distances at higher voltages over thin,…

Nearly a century ago, the Tennessee Valley Authority (TVA) brought electricity to a part of the country that was desperate for help. Established on May 18, 1933, the TVA covers most of Tennessee and parts of the six surrounding states: Alabama, Georgia, Kentucky, Mississippi, North Carolina, and Virginia. Today, it provides power service across 80,000 square miles, and it provides electricity to nearly 10 million people. COBBLESTONE talked with historian Pat Bernard Ezell and public relations spokesperson Scott Fiedler about how the TVA transformed the region. Can you describe what was going in the United States before the TVA was established in 1933? As you know, the Great Depression was taking place across the United States. There were bank failures in 1929. But as bad as conditions were elsewhere in…

Today, many girls are interested in becoming scientists. A century ago, however, young women were not encouraged to study science and mathematics. This month’s mystery hero was an exception. Our hero’s father was tragically killed by a burglar just weeks before she was born on January 10, 1898. Our hero’s mother raised her and her brother. She moved the family to New York City and then to France. She wanted her children to be bilingual, learning both French and English. Our young hero became proficient in both languages. The family returned to New York when our hero was 14 years old. She entered the Rayson School. It was an exclusive private school in which girls and boys took the same academic classes. Our young hero had a passion for mathematics,…

Benjamin Franklin is remembered today for many things. He was a Founding Father, who participated in the creation of the United States. He also earned fame as a writer, a civic leader, a businessman, and a diplomat. And he became internationally famous as a scientist for his experiments with electricity. Electric experiments were enjoyed as entertainment in Franklin’s day. And Franklin knew how to have fun with them. Guests attending a party at his home might be treated to the sight of his silverware giving off sparks! But Franklin also was quite serious about electricity. His experiments in the 1740s led him to become the first person to use the terms “positive” and “negative” when referring to an electric charge. He was the first person to describe the transfer of…

The electricity we need to power our lives is generated in a power plant or station. In a typical power plant, pressurized steam powers a turbine. The turbine spins a magnet (usually an electromagnet) inside wire coils. The spinning magnet alternately exposes the wire to its north and south poles. Each half spin changes the current’s direction. A turbine in a North American power plant rotates 3,600 times per minute. Thus, its alternating current (AC) switches direction back and forth 60 times per second. A power plant distributes the electricity it generates by sending it along high-voltage power lines. Those transmission lines are held up by massive metal towers called pylons built in a long line across the land. Electric power is the voltage times the current. Voltage is basically…

The future is now. Both the U.S. federal government and the auto industry agree that  the time has come for clean cars to get in the fast lane. Here’s a look at how electric vehicles (EVs) and hybrids are leading the way. EVs vs. Hybrids EVs are vehicles that run only on electricity. They’re also known as plug-ins—they plug into charging stations to power up on electricity. A powerful battery stores the energy. On average, an EV has a range of about 200 miles before the battery needs to be recharged. The recharging process could be as short as an hour or as long as an overnight. Right now, electric vehicles face two big challenges. They have limited range and cost a lot—more than a gas-powered luxury car. The electric…

Lightning Storm Harriet Tubman The Yukon Gold Rush Famous Islands Draw a picture or write a poem or short essay that connects to one of the above COBBLESTONE themes on which we currently are working. All contributions must be your original work. Include a note from a parent or a legal guardian clearly stating: “This is my child’s original work, and COBBLESTONE has permission to publish it with my child’s name, age, and hometown, in print and online.” We will include as many as we can in the upcoming issue to which your work relates. Mail it to the address shown here, or email it to cobblestone@cricketmedia.com. A Haiku Boom. Snap. Crash. Kapow. The power has gone out again! Lightning will take over. Eden Perman, age 10 Chicago, Illinois…

Our lives have been made easier by harnessing the power of electricity. Electricity provides the power to light, heat, and cool our homes. It allows us to communicate with distant family members through our charged cell phones and computers. But while it improves our daily lives, electricity can be dangerous. To use this powerful force safely, follow these tips. • Never combine electricity and water. Technically, pure water does not conduct electricity, but most bodies of water or tap water are not pure water. Those sources will conduct electricity. The results can be deadly. • Never swim when you hear thunder or see lightning. Get out of the water immediately. In fact, it’s best to get safely indoors when a storm is approaching. • Never use or turn on any electrical appliances while…

Benjamin Franklin once tried to harness the power of electricity to cook his dinner. After experimenting on a few unlucky smaller birds, he attempted this feat on a fully grown turkey. But all Franklin got was a severe, evening-ending shock, while the turkey strutted away unharmed. The first electric cars were invented in the 1830s. That’s more than 60 years before Henry Ford started mass-producing gasoline-powered vehicles. By 1900, an electric car held the world speed record at 66 miles per hour. Electric cars were quiet and simple to operate, but they were expensive and had only a short range. Internal combustion-powered vehicles quickly took over. A few animals use electricity in their quest for food. The bill of the platypus and the snout of the echidna (also known as…

Can you solve this puzzle about electricity? All the answers can be found in this issue. The solution is on page 49. ACROSS 3. Lewis H. _____ was one of the few African Americans to play a major role in early electricity-related discoveries. 5. A _____ is a machine that pulls a fast-moving element through its paddles or blades to produce continuous power. 7. Coal, oil, and natural gas are examples of _____ _____, which produce about 60 percent of the United States’ electricity. 9. _____ current travels only in one direction and works best over short distances. 11. An electric _____ is a massive, interconnected network of power stations and lines that safely delivers electricity to consumers. DOWN 1. This type of car is powered by both a gasoline…

Electricity is “the form of energy from the existence of charged particles (such as electrons or protons) where particles with opposite charges attract and particles with the same charge repel.” The electric charges can be stationary (static) or moving (current). Another meaning of electricity is “intense, contagious emotional excitement.” Electric derives from the New Latin word electricus, which means “deriving from amber (as from rubbing).” The Latin word for “amber” is electrum. Static electricity is “electricity that is produced by friction or the rubbing of a surface of an insulated body that remains until it is discharged.” For example, a person who drags his or her socked feet across a carpet can produce static electricity that is discharged when the person touches a new object. Static means “bodies being at…