
Electricity from Clean Energy sources- UW
Quiz by AKHILA APPU LAILA
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What do people need to light their homes and drive cars? Energy! It gives power to many things we need and use.
Now more people are using clean energy. Such energy does not pollute the air. Two kinds of clean energy are wind power and solar power. Solar means “from the sun.” The sun gives Earth heat and light. Some homes have solar panels on the roof. The panels collect sunlight and turn it into electricity. That is a kind of energy.
People can turn wind energy into electricity. Wind turbines are machines that spin when the wind blows. They make electricity.
Hydroelectric energy is made by moving water. Hydro comes from the Greek word for water. Generators are machines that produce electricityHydroelectric energy has been in use for thousands of years.
Q1. ______________________ are used to create solar energy.
Wind turbines
Solar panels
What do people need to light their homes and drive cars? Energy! It gives power to many things we need and use.
Now more people are using clean energy. Such energy does not pollute the air. Two kinds of clean energy are wind power and solar power. Solar means “from the sun.” The sun gives Earth heat and light. Some homes have solar panels on the roof. The panels collect sunlight and turn it into electricity. That is a kind of energy.
People can turn wind energy into electricity. Wind turbines are machines that spin when the wind blows. They make electricity.
Hydroelectric energy is made by moving water. Hydro comes from the Greek word for water. Generators are machines that produce electricity. Hydroelectric energy has been in use for thousands of years.
Q2. Wind turbines turn wind energy into __________ .
Electricity
heat and light
Read the passage and answer
What do people need to light their homes and drive cars? Energy! It gives power to many things we need and use.
Now more people are using clean energy. Such energy does not pollute the air. Two kinds of clean energy are wind power and solar power. Solar means “from the sun.” The sun gives Earth heat and light. Some homes have solar panels on the roof. The panels collect sunlight and turn it into electricity. That is a kind of energy.
People can turn wind energy into electricity. Wind turbines are machines that spin when the wind blows. They make electricity.
Hydroelectric energy is made by moving water. Hydro comes from the Greek word for water. Generators are machines that produce electricityHydroelectric energy has been in use for thousands of years.
Q1. ______________________ are used to create solar energy.
What do people need to light their homes and drive cars? Energy! It gives power to many things we need and use.
Now more people are using clean energy. Such energy does not pollute the air. Two kinds of clean energy are wind power and solar power. Solar means “from the sun.” The sun gives Earth heat and light. Some homes have solar panels on the roof. The panels collect sunlight and turn it into electricity. That is a kind of energy.
People can turn wind energy into electricity. Wind turbines are machines that spin when the wind blows. They make electricity.
Hydroelectric energy is made by moving water. Hydro comes from the Greek word for water. Generators are machines that produce electricity. Hydroelectric energy has been in use for thousands of years.
Q2. Wind turbines turn wind energy into __________ .
What do people need to light their homes and drive cars? Energy! It gives power to many things we need and use.
Now more people are using clean energy. Such energy does not pollute the air. Two kinds of clean energy are wind power and solar power. Solar means “from the sun.” The sun gives Earth heat and light. Some homes have solar panels on the roof. The panels collect sunlight and turn it into electricity. That is a kind of energy.
People can turn wind energy into electricity. Wind turbines are machines that spin when the wind blows. They make electricity.
Hydroelectric energy is made by moving water. Hydro comes from the Greek word for water. Generators are machines that produce electricity. Hydroelectric energy has been in use for thousands of years.
Q3. Identify the following statement as True / False
Hydroelectric energy is not a clean energy used to produce electricity.
Can you imagine what life would be if we run out of electricity? Very good! We cannot enjoy different electrical appliance anymore. OBJECTIVES: - Enumerates ways to conserve electrical energy. - Practices ways to conserve electricity. SCIENCE 2 – MODULE 6 SEIBO COLLEGE 21 Electricity gives us a comfortable life. It can help us do our work easier and faster through the use of different appliance or machines. Have you experienced brownout? Do you know why this happens? Brownout happens when there is a loss of electrical power in a specific area. To prevent this from happening, we must conserve electrical energy. How can we do that? Below is a list of ways on how we can conserve electricity. Read and understand it carefully. Ways of Conserving Electrical Energy at Home 1. Turn off and unplug electrical appliance when not in use. 2. Replace old bulbs with energy saving fluorescent bulbs. 3. Clean or dust your fluorescent lamp to give more light. 4. Turn off the light when leaving your room. 5. Avoid frequent opening of your refrigerator’s door. 6. Iron clothes once a week in the cooler part of the day. 7. Wash clothes using washing machine once a week. 8. Limit yourself to two hours of computer use a day. 9. Avoid using the microwave oven very often
Environmental Protection — Vocabulary Quiz (B1+) 🧠 1. What does “renewable energy” mean? a) Energy that never runs out and comes from nature 🌞 b) Energy that comes only from coal and oil c) Energy that can’t be used again d) Energy made from plastic ✅ Correct answer: a) Energy that never runs out and comes from nature 🌞 🧃 2. What are “single-use plastics”? a) Plastics that can be recycled many times b) Plastics used once and then thrown away 🚯 c) Plastics that last forever d) Plastics used only for energy production ✅ Correct answer: b) Plastics used once and then thrown away 🚯 🗑️ 3. What is “waste”? a) Things we eat b) Things we throw away because we don’t need them ♻️ c) Energy from the sun d) Clean water and air ✅ Correct answer: b) Things we throw away because we don’t need them ♻️ 🌱 4. What does “reduce” mean in the context of environmental protection? a) To use more of something b) To make or use less of something 🔽 c) To destroy nature d) To create pollution ✅ Correct answer: b) To make or use less of something 🔽 ♻️ 5. What does “recycle” mean? a) To use materials again instead of throwing them away b) To burn plastic waste c) To stop using energy d) To clean streets ✅ Correct answer: a) To use materials again instead of throwing them away 💬 6. Choose the correct sentence: a) We should recycle waste to protect the environment. ✅ b) We should throw away all plastic bottles. c) Renewable energy is bad for nature. d) We need more single-use plastics in our cities. ✅ Correct answer: a) We should recycle waste to protect the environment. 🌿 7. Fill in the blank: We can ______ pollution if we use public transport and save electricity. a) recycle b) reduce c) waste d) throw ✅ Correct answer: b) reduce 💡 8. True or False: “Solar and wind power are examples of renewable energy.” ✅ Answer: True ☀️💨 🏆 9. Which of these actions helps protect the environment the most? a) Using renewable energy b) Buying single-use plastics c) Producing more waste d) Throwing rubbish in the street ✅ Correct answer: a) Using renewable energy 🌎 10. Complete the sentence: People should ______ paper, glass, and plastic to keep the planet clean. a) waste b) reduce c) recycle d) ignore ✅ Correct answer: c) recycle
Alright, Isti — here’s a longer and more detailed English version of the Isaac Newton text, still written at a level that’s accessible for Grade 4 students, but rich enough in information to meet PISA literacy expectations and EF A2-level vocabulary. I’ve kept sentences short, clear, and with explanations for new concepts so it’s easier for young learners to follow, while still including both famous facts and lesser-known stories. ⸻ Isaac Newton: The Man Who Changed the Way We See the World A Boy from a Small Village Isaac Newton was born on January 4, 1643, in Woolsthorpe, a small village in England. His life was not easy. His father died before he was born. When he was just a few months old, his mother remarried and left him to live with his grandmother. Isaac missed his parents, but he kept himself busy by making things and exploring the world around him. As a child, Isaac liked to build models and machines. He made a small windmill that could turn with the wind. He built a water clock that told the time by dripping water into a container. He even made a sundial — a clock that tells the time by using the shadow of the sun. 💡 Did you know? The sundial marks that Isaac carved as a boy can still be seen today on the wall of his old house. ⸻ School and Curiosity When Newton first went to school, he was not the top student. At first, he did not pay much attention in class. But one day, another boy teased him for not being smart. Newton decided to study hard to prove him wrong. Soon, he became the best in his class. Isaac loved asking questions. He wanted to know how and why things happened. He enjoyed watching the stars at night and thinking about how the world worked. ⸻ The Falling Apple and Gravity One of the most famous stories about Newton is the falling apple. One afternoon, Isaac sat in his mother’s garden and saw an apple drop from a tree. This made him think: “Why does the apple fall straight down? Why doesn’t it fly up into the sky?” From this question, Newton began to think about gravity — an invisible force that pulls objects toward each other. Gravity is what keeps our feet on the ground. It’s also what keeps the Moon moving around the Earth and the planets moving around the Sun. 💡 Fun fact: The apple did not hit Newton’s head. That’s just a story people made up later to make the tale more exciting. ⸻ Newton’s Three Laws of Motion Newton studied movement and wrote three important rules: 1. Objects stay still or keep moving unless something makes them change. • Example: A ball will not roll unless you push it. 2. The bigger the push, the bigger the movement. • Example: If you kick a ball harder, it will go faster and farther. 3. Every action has an equal and opposite reaction. • Example: When you jump off a boat, the boat moves backward as you move forward. These three laws are still used today to understand how cars, rockets, and even roller coasters work. ⸻ Discoveries in Light and Color Newton also studied light. He found that white light is not just one color — it is made of many colors. He used a glass prism to split sunlight into a rainbow. This helped scientists understand how colors work. ⸻ Inventions and New Ideas Newton made a special telescope that used mirrors instead of lenses. This type of telescope made images of planets and stars much clearer. It is still called the Newtonian telescope today. He also worked in mathematics and helped create a new type of math called calculus, which is used to study changes and movement. ⸻ Strange Experiments Newton was so curious that he sometimes tested ideas on himself. Once, he put a thin needle, called a bodkin, beside his eye to see how it would change his vision. It was very dangerous, but luckily he did not go blind. 💡 Did you know? Newton also studied alchemy — an old kind of science where people tried to turn metal into gold. He never succeeded, but it showed how wide his interests were. ⸻ Later Life and Work At the age of 27, Newton became a professor at Cambridge University. He later worked for the Royal Mint, making sure coins were made safely and stopping people from making fake money. He was very strict, and some criminals were sent to prison because of his work. Newton never married. He spent most of his life reading, writing, and doing experiments. ⸻ The End of His Life Isaac Newton died in 1727 at the age of 84. He was buried in Westminster Abbey, a famous place in London where great people of Britain are honored. His work changed the world forever. Even today, scientists, engineers, and students still use Newton’s laws and ideas. 💬 Newton once said: “If I have seen further, it is by standing on the shoulders of giants.” This means we can make new discoveries by learning from the work of others who came before us. give 10 questions to each passage with PISA literacy standard for kid 10 years, 1. Nikola Tesla: The Man Who Dreamed of Lightning Born: July 10, 1856 Died: January 7, 1943 When Nikola Tesla was a boy in Croatia, he saw a flash of lightning and asked his mother, “Can we catch the light?” That question never left him. As he grew older, Tesla became a brilliant inventor, especially fascinated by electricity. He believed in a future where energy could be sent wirelessly through the air—like music through the radio! Tesla invented the alternating current (AC) system, which became the foundation of modern electricity. At the time, Thomas Edison promoted direct current (DC), and the two men had a fierce competition. Many laughed at Tesla's bold ideas, but he never gave up. He dreamed of wireless communication, flying machines, and even free energy for everyone. Though he died alone and poor, today the world honors his vision. Think About It: Why do you think people didn’t believe Tesla at first? What can we learn from Tesla’s courage to dream big? 2. Charles Darwin: The Man Who Studied the World’s Weirdest Creatures Born: February 12, 1809 Died: April 19, 1882 When young Charles Darwin got on a ship called HMS Beagle, he didn’t know he would change science forever. He sailed around the world for five years, collecting plants, animals, and fossils. On the Galápagos Islands, he noticed something curious: finches had different beaks depending on their island. Why? Darwin’s observations led him to write the theory of evolution by natural selection. It explained how animals adapt and survive. But his ideas shocked many people because they seemed to challenge religious beliefs. Despite the controversy, Darwin continued his work. His book On the Origin of Species changed how we see life on Earth. Think About It: Should scientists share their ideas even if they go against what others believe? How did traveling help Darwin make new discoveries? 3. Marie Curie: The Woman Who Glowed in the Dark Born: November 7, 1867 Died: July 4, 1934 Marie Curie was born in Poland at a time when girls were not allowed to study science. But that didn’t stop her. She moved to France, worked day and night, and discovered radioactivity, a powerful energy hidden inside atoms. She and her husband, Pierre Curie, found two new elements: polonium and radium. She became the first woman to win a Nobel Prize, and the only person to win in two different sciences: physics and chemistry. Even when Pierre died in an accident, Marie continued their work. Her discoveries helped doctors treat cancer—but working with radioactive materials also harmed her health. She died from radiation exposure, but her legacy lives on. Think About It: What challenges did Marie Curie face as a woman in science? Why is it important to balance discovery with safety? 4. Galileo Galilei: The Star Watcher Who Defied the Church Born: February 15, 1564 Died: January 8, 1642 Galileo loved looking at the stars. He built one of the first powerful telescopes and made stunning discoveries: mountains on the Moon, moons around Jupiter, and that the Earth orbits the Sun—not the other way around. This idea, called heliocentrism, went against the teachings of the Church. He was put on trial and forced to say he was wrong. But he wasn’t. He spent his last years under house arrest, quietly writing. Today, Galileo is called the father of modern science for daring to question what others blindly believed. Think About It: Why do you think Galileo was punished for telling the truth? Should science always follow evidence, even if it goes against powerful beliefs? 5. Isaac Newton: The Man Who Asked “Why?” When an Apple Fell Born: January 4, 1643 Died: March 31, 1727 One day, an apple fell from a tree, and Isaac Newton began to wonder: Why did it fall down, not sideways or up? This simple question led to his theory of gravity. Newton also invented calculus, described the laws of motion, and changed physics forever. But Newton wasn’t just a genius—he was curious, quiet, and often worked alone. He believed everything in nature followed rules, and it was our job to discover them. Thanks to him, we understand how planets move, how rockets launch, and why you fall when you trip. Think About It: How did Newton’s curiosity lead to great discoveries? Do you think working alone helped or hurt Newton? 6. Ada Lovelace: The First Computer Programmer Before Computers Existed Born: December 10, 1815 Died: November 27, 1852 Ada Lovelace was the daughter of the famous poet Lord Byron, but she didn’t love poetry—she loved numbers! At a time when girls were expected to sew, Ada studied mathematics. She met Charles Babbage, who designed an early computer called the Analytical Engine. Ada imagined the machine could do more than just math—it could create music, art, and even write! She wrote what is now considered the first computer program, long before real computers were built. Think About It: How did Ada imagine something that didn’t exist yet? Why do we call her a pioneer in technology? 7. Albert Einstein: The Man Who Brought Time and Space Together Born: March 14, 1879 Died: April 18, 1955 Albert Einstein wasn’t always a good student. In fact, his teachers thought he was slow. But Einstein thought deeply. He asked big questions like, “What if you could ride a beam of light?” His theories of relativity changed how we see space, time, and gravity. He also warned the world about the dangers of nuclear weapons, even though his ideas helped create them. Einstein believed science should help people, not harm them. With his messy hair, kind smile, and brilliant mind, he remains a symbol of genius. Think About It: Can someone be bad in school but still be brilliant? Should scientists be responsible for how their inventions are used? 8. Pythagoras: The Musician Who Loved Math Born: Around 570 BC Died: Around 495 BC Long ago in ancient Greece, Pythagoras believed the universe followed numbers. He discovered the Pythagorean Theorem, a rule about triangles that helps us build houses, design computers, and navigate space. He also believed that music had math inside it—that certain notes made perfect harmony because of mathematical ratios. Pythagoras started a secret school and taught his students to search for truth through numbers, shapes, and sound. Think About It: Why do you think Pythagoras saw math in everything? How does music relate to math? 9. Rosalind Franklin: The Woman Behind the DNA Discovery Born: July 25, 1920 Died: April 16, 1958 Rosalind Franklin loved looking closely at things. She used a special machine called X-ray crystallography to photograph molecules. One of her greatest photos, called Photo 51, showed the shape of DNA, the molecule that carries life’s instructions. But her work was taken without credit. Two men, Watson and Crick, used her photo to build their famous model of DNA and won the Nobel Prize. Rosalind died young and never knew how important her work became. Think About It: Why is it important to give credit in science? What can we learn from Rosalind’s quiet strength? 10. Carl Linnaeus: The Man Who Gave Names to Everything Born: May 23, 1707 Died: January 10, 1778 Have you ever wondered why a tiger is called Panthera tigris? That’s thanks to Carl Linnaeus, a Swedish scientist who created a way to name and organize every living thing. His system is still used today in biology. Linnaeus loved nature and spent his life collecting plants, animals, and even rocks. He believed that by organizing life, we could better understand it. Thanks to him, we now have a global “dictionary of nature.” Think About It: Why is it important to name and organize living things? How does order help us understand the world?
All About Kites Introduction. A kite is one of the oldest toys. And it's very simple to make. Kites come in many sizes, shapes, and colors. Did you know that kites can be both toys and tools? History of Kites. Kites were named after the kite bird. The kite bird has wide wings and easily floats high in the sky. No one knows who made the first kite. But one famous Chinese story about a kite was written over 2,000 years ago. The story is about a man who used a kite to attack a fort. He couldn't find a way to get inside the fort. So he tied himself to a huge kite. He flew over the wall of the fort and scared the soldiers! The inventor Ben Franklin had the idea that lightning was made of electricity. He wanted to prove his idea. One day when it was stormy, he tied a metal key to a kite string. Then he flew the kite up into the storm clouds. Lightning from the storm hit his kite. The electricity ran down the wet string to the metal key. When he reached for the key, he got a surprise. The electricity jumped from the key and gave him a shock! Do not try this yourself. It's not safe to do. When Ben Franklin tried to do it again, he was hurt badly. Many Uses for Kites. Some people have used kites for fishing. They put a fishhook and bait on the long kite tail. The kite tail dragged in the water. When a fish saw it, it bit the bait and was caught on the hook. Then the kite was pulled in. Weather kites carried scientific gauges into the sky. The gauges measured how fast the wind was blowing and how cool the air was. Years ago, some armies used kites with cameras to spy on enemy troops. Kites were also used as flying targets. The kites trained soldiers to aim better. Soldiers shot at the kites. The moving kites were hard to hit with bullets. Different shapes of kites fly in different ways. Flat, diamond-shaped kites fly easily. Box-shaped kites can hang still in the air for a long time. Stunt kites twist and twirl on many strings. Large parafoil kites act almost like parachutes. Giant dragon kites flutter. Fighting kites can be used to cut other kites' strings. On a breezy day, take your kite to a flat, open area. Be sure that there are no power lines or big trees. Look at the ground around you. Is there anything you could trip over? Hold your kite up by the bridle and run into the wind. Let go of the kite and slowly let out some string. Then let out a little more until your kite is high in the sky. Happy flying!
Manual vice steward avenge Operated or done with your hand rather than with electricity or machines. Inflict harm in return for an injury or wrong doing to oneself or another. Immoral or harmful behavior. Someone who looks after something and protects it. monstrous menace shuffle infer To walk slowly, without lifting your feet completely from the ground Something that is dangerous or can cause harm. To draw a conclusion after considering all the facts. Ugly and frightening.
Create a reading comprehension quiz based on the following text: Not many people 'have heard/ heard of Nikola Tesla, who 2played/was playing a key role in creating the alternating current (AC) supply of electricity we are having/ have in our homes today. Early in his career, Tesla has worked / worked with Thomas Edison. He had emigrated/ has emigrated to the USA from Europe in 1884. While Tesla was working/ had worked for Edison, they had an argument over payment for an invention, so Tesla was deciding/ decided to work independently. It was then that he developed a motor that could produce an alternating current. Throughout his life, Tesla continued to conduct experiments and helped / was helping develop X-ray radiography and wireless communication. There is no doubt that he has had / had had a large impact on modern technology. Many of the gadgets that we 10 are enjoying/enjoy today would not have been possible without Nikola Tesla.
Communication is the process of passing information, news, ideas or feelings from one person to another. For communication to take place, there must be a sender and a receiver of the message. System of communication is the different ways in which messages are sent and received. THE FOLLOWING ARE THE MAIN MEANS OF COMMUNICATION: 1.Traditional means: These are the means used to pass ideas or information in the past. The following are the various means used: Drumming, Message Carrier, Town Criers, Smoke Signal, Gun Shots, sending of symbolic items (such as a gun or bullets to announce war, Sponge and Soap to announce the safe delivery of a pregnant woman). 2. Modern means: These are the means used to pass ideas or information in the present day. The following are the various means used: Radio, Television, Telephone, Newspapers and Magazines, The Internet, Fax machine, Handsets, Telegram, Satellite, Road signs, Posters and billboards. DIFFERENCES BETWEEN TRADITIONAL AND MODERN MEANS OF COMMUNICATION. Traditional means Modern means 1.It makes use of local items such as drum, gong etc. It makes use of modern technology 2.Messages cannot travel very long distances. Messages can travel far and wide. 3. Delivery of message is slow. It may take days or weeks or months. Delivery of message is faster. Can reach the recipient within seconds. 4. It is cheaper It is very expensive. 5.It does not use electricity. It uses electricity. A recipient is the person or people receiving a message. While the sender is the person or people who sends the message.
What is Electric Force? Electric force is just one of many types of forces in the world of physics. Forces are how and why things move, and can be explained by Newton's Laws of Motion. On the smallest scale, electric force is the resulting interaction between two charged particles. These charges can be either positive or negative. Larger objects can be charged by having an abundance of either of these particles, and therefore can create an electric force on a larger scale. Electric force is the reason why hair will sometimes stand up on its own and is also why we have electricity, allowing us to live in the modern world with lights and technology. Even out in nature electric force is present, as electric force causes lightning to strike. Electric force is fundamental to our everyday way of living. Reviewing Newton's Laws of Motion Newton's Laws of motion are the basic principles or ground rules that are applied all across physics. They describe how objects move and can be used to describe the interaction of charges. They are the following: An object in motion will stay in motion unless an external force is applied The force exerted on an object is equal to the mass times the acceleration of the object. ( ) Every force has an equal and opposite force Newton's laws explain how and why charged particles move. Since there is a force involved (e.g. electric force), particles will move around, which is explained by the first law. The second law describes how acceleration of charges can be calculated once the electric force is known. The third law explains how attractive and repulsive forces between charged objects are equal and opposite. Electric Force Examples and Types of Charge As previously mentioned, there are only two types of charges; positive and negative. Two like charges will repel (or move away from) each other, and two opposite charges will attract (or move towards) each other. In other words, two positive or two negative charges will repel, while a positive and a negative charge will attract. Opposite charges will attract while like charges will repel. Attraction versus Repelling Forces Notice how the forces acting upon each other are equal and opposite, as Newton's third law states. Both charges are exerting forces onto each other. Charges in Atoms An atom is made up of three types of particles; protons, neutrons, and electrons. Protons have a positive charge, neutrons have no charge, and electrons have a negative charge. There are no positive or negative charges smaller than protons and electrons. Objects on a larger scale result in an overall positive or negative charged due to an uneven distribution of protons to electrons. An atom consisting of more protons than electrons would be considered positive, and an atom with more electrons than protons would be considered negative. Protons are held close to the nucleus and are tightly bound to an atom, so it's difficult for protons to escape an atom. Electrons, on the other hand, are much further away from the nucleus of an atom. This makes it much easier for them to be removed from an atom. Electrons can leave or join atoms, making them positive or negative depending on the amount of protons. Similarly, for the bigger picture, overall materials and objects with more electrons than protons would be considered negative, and vice versa. Electric Force Examples Hair standing up: When hair is brushed, the hairbrush can strip electrons from hair strands, resulting in the hair being positively charged. This addition of electrons to the hairbrush in turn makes the hairbrush negatively charged. Since the hair is now positively charged, and like forces repel, hair strands will move away from each other, resulting in the hair standing up. Current electricity: All of our everyday technology is powered through current electricity, which is the consistent flow of electrons through conductive materials. This flow is caused by the electric force, as the electrons flow from a negative source to a positive source. Lightning: During a storm, it is common for an abundance of electrons to build up on the bottom of a cloud, making that part of the cloud negatively charged. Positive charges in the ground start to gather on the surface or even on tall objects such as trees as they are attracted towards the negatively charged undersides of clouds. Lightning strikes as a result of these charges becoming extremely built up. Lightning is caused by electric force Lightning Electric Force Equation: Coulomb's Law The magnitude of the electric force, or the amount of force in which objects repel or attract, depends on the distance between the two charged objects and the amount of charge each object carries. The electric force is stronger the closer together the two charges are, and weaker as the two charges move apart. Electric force is also stronger with more charge, and weaker with less charge. This effect on electric force is predictable, and is known as Coulomb's Law. It can be calculated using a mathematical equation, and the resulting magnitude of electric force is measured in Newtons. Coulomb's Law Electric force can be calculated using the following equation known as Coulomb's Law: In this equation, F is the electric force measured in newtons, K is a constant known as the electrostatic constant, and are charges one and two measured in coulombs, and is the radial distance in meters between the two charges. Since the distance is squared and on the denominator, the electric force drops off exponentially as charges move away from each other. This means that the Electric force is inversely proportional to distance. As charges move away from each other, the electric force between them gets smaller and smaller, until the force is negligible. The amount of charges are in the numerator of this equation, making the magnitude of the force larger with more charge. This means that the force is directly proportional to the amount of charge. When the charges are smaller, the amount of force will be smaller. When there is a lot of charge, the force will be much greater. When calculating the electric force using Coulomb's law, the resulting answer only gives the magnitude of the force and not the direction. In order to know the direction, you must know the types of charges. Once again, like forces repel, and unlike forces attract. It helps to draw a visual representation, or a free-body diagram, of the charges and forces acting upon them in order to understand the resulting force direction. Electric Field versus Electric Force An electric field is a direct result of an electric force. Its pure definition is electric force per unit charge, and can be thought of as a mapping of the force vectors. An electric field is present anytime there is an electric force. Therefore, when there are two or more charged particles, there is a surrounding electric field. The direction of the electric field is the direction a positive charge would flow if it were placed within the field. The electric field moves out from a positive charge and goes into a negative charge. Particles with unlike charges move towards each other, and their corresponding electric field lines move out from the positive charge and into the negative charge. The strength of the force at any given point can be seen through the spacing of the electric field lines. The electric force is strongest where the electric field lines are closest together, and weaker as these lines move apart. Like Coulomb's law expresses, electric field lines show how the electric force is strongest with a minimum distance between the two charges. Unlike charges will result in a repelling force, and the resulting electric field is a visual representation of this effect. Electric fields of two positive charges have the electric field moving out away from both of them. As with two negative charges, the field lines move in towards each negative. Lesson Summary An electric force is created when there are two or more charged particles or objects. These charges can be either positive or negative. Like charges will attract (move towards each other) while unlike charges will repel (move away from each other). As Newton's third law suggests, the forces acting upon each other are both equal and opposite. Electrons and protons within an atom are the two smallest types of charges there are. Electrons carry a negative charge while protons carry a positive charge. Electrons can be easily removed or added to atoms, making the overall charge positive or negative. Objects with more electrons than protons are negatively charged. Electric force is strengthened with increased charge and a shorter distance between the charges. This effect is known as Coulomb's law and can be calculated with the Coulomb's law equation. The magnitude of the force is measured in Newtons, and the direction can be determined by knowing whether the charges are attracting or repelling each other. An electric field is present wherever there is an electric force. The direction of this electric field is the direction a positive charge would flow if it where to be dropped in the field, which is from the positive to the negative.