Helping Kids Understand Sir Isaac Newton’s Three Laws of Motion

By Lorie Moffat

Your son or daughter has science questions about Sir Isaac Newton’s three laws of motion. How can you begin to guide your child’s understanding of these concepts? Without thinking about them, we use Sir Isaac Newton’s three laws of motion every day. Newton’s first law explains why it is harder to stop a moving car than a roller skate. Newton’s second law algebraically relates the force on an object, its mass, and its acceleration. Newton’s third law concerns how forces act upon objects. By relating every day experiences, you can help your child understand Sir Isaac Newton’s three laws of motion.

Newton’s first law of motion is also known as the law of inertia. The term, inertia, derives from the Greek, inert, or not moving. Newton’s first law states that any object will remain stationary or will continue to move in a straight line unless it is acted upon by an external, unbalanced force. A force is a push or pull on an object. Inertia is a measure of the mass of an object. An automobile has more inertia than a roller skate. While you are traveling in a moving car, you are moving in the same direction and with the same speed as the car. If the car suddenly comes to a stop, you will still be moving in the original direction, through the windshield if you do not use a seatbelt or airbag. The seatbelt keeps you in one position relative to the car’s motion, keeping your body against the seat. Inertia also explains why you lean towards the opposite direction as the car moves around a steep curve. If the car turns right, you lean towards the left; if the car turns left, you lean towards the right. Again, your body continues to move in a straight line during the turn, as it did before the turn.

Any time you want to change the speed or direction of an object, you need to use the appropriate force. Newton’s second law of motion relates the concepts of mass, force, and acceleration. In science, acceleration is the change in speed or direction of a moving object. Force on an object is equal to its mass multiplied by its acceleration. The strength of the force on an object depends upon the object’s mass, or how much material it contains, and how fast its speed is changing, or its acceleration. An automobile hitting a wall at the same speed as a roller skate would have more force, since the car has more mass. A unit of measurement for force is the Newton, abbreviated N, named after Sir Isaac Newton. One Newton, or one N, is the force needed to move a mass of one kilogram one meter per second in a second. Or algebraically,

1 N  =      1 kg   m


s2

A Newton of force is a small amount. A person weighing 110 pounds exerts a force of 50 Newtons on Earth.

Newton’s third law of motion is more commonly called action reaction. For every action in one direction, there is an equal and opposite reaction in the opposite direction; even if the object does not move. Forces always act in pairs, even if the object remains still. While sitting in a chair, you provide a force on the chair acting down towards the floor. At the same time, the chair provides an equal and opposite upward force on you. If this were not the case, you would be sitting upon the floor instead. While you walk, for each step that you take your foot pushes against the floor. As you push, or provide a force, against the floor, the floor also pushes against your foot, propelling you forward. If you try to walk across sheer ice, you must adjust your steps, since the ice does not provide the same force as the floor.

By using every day examples, you can help your children understand Sir Isaac Newton’s three laws of motion. The law of inertia, or Newton’s first law of motion, describes how a stationary object begins to move or how the motion of an object changes. Newton’s second law of motion algebraically relates an object’s mass and acceleration to the amount of force involved to cause motion. Finally, Newton’s third law of motion involves the fact that forces on an object always act in opposing pairs, whether or not the forces cause motion.

Lorie Moffat has 20 years of teaching experience in both public school classroom and science museum settings.

Source: http://www.homeschool-articles.com/helping-kids-understand-sir-isaac-newton%e2%80%99s-three-laws-of-motion/

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Teaching Children about the Six Kinds of Potential Energy

By Lorie Moffat

Your son or daughter has questions about the different kinds of potential energy, or energy that is stored. It can be quite confusing since some examples are not stationary on a molecular level. Some types are actually potential and kinetic (energy of motion) simultaneously, like heat or chemical. You can explain the differences between the six kinds of potential energy to your child using common examples.

Potential energy, or the energy of position, is stored energy. That is, it has the capacity to do work or to move something in a scientific sense. There are many types of potential energy including gravitational potential, electrical, chemical, thermal, magnetic, and elastic.

  • Six Kinds of Potential Energy #1 – When an object such as a ball is on the slope of a hill, it has gravitational potential energy based upon its height from the bottom of the hill, its mass, and the gravitational constant, g, which on Earth is 9.8m/s2. The gravitational constant is a form of acceleration. The higher an object is above the Earth’s surface, the more it will accelerate as it falls until it reaches terminal velocity (or the fastest speed at which it will fall). If a ball with the mass of 10 kilograms is 100 meters above the Earth’s surface, its gravitational potential energy will be the product of mass, gravitational constant, and height; or (10 kg) (9.8 m/s2) (100m), which is 9800 kgm2/s2 or 9800 Newton-meters or 9800 Joules. A Joule, which rhymes with rule, is the metric unit for energy. A ball’s potential energy changes to kinetic as it rolls or falls downhill.
  • Six Kinds of Potential Energy #2 – Electrical energy is stored in a battery in the chemical elements the battery contains. One battery terminal has an element that allows electrons to flow from it while the other terminal has an element that readily accepts electrons. A battery eventually stops working because the chemicals get used up. Static electricity involves objects like a balloon or the family’s pet cat that have extra electrons, especially in dry weather. If you rub a balloon on your hair and stick it to the wall, that’s using static electricity. When you pet the cat on a dry day, you may hear a crackling sound or see tiny sparks which is also static electricity.
  • Six Kinds of Potential Energy #3 – Chemical energy is trapped in chemical bonds. It is the component of the energy that can be released when molecules interact during a chemical reaction. It includes fossil fuels like coal, oil, natural gas and wood. Chemicals are composed of molecules, which are composed of atoms, which are composed of protons, neutrons, and electrons for practical purposes. Electrons are in constant motion circling the protons and neutrons in the nucleus. The motion of electrons is involved with chemical bonds creating molecules. During a chemical reaction this energy gets stored. Our cells need the chemical energy stored in the foods that we eat in order to function properly. Digestion is a slow process that breaks down the food we eat, releasing energy for the body’s use. The energy from foods becomes heat, carbon dioxide and water. Food packages list the number of Calories in the product. One Calorie of food energy is 4180 Joules.
  • Six Kinds of Potential Energy #4 – Thermal or heat energy is in all matter. Even something that feels cold like an ice cube still has heat. The molecules of all matter moves even as part of a solid. As long as the temperature of a material is above absolute zero, which is -459 degrees Fahrenheit, it has heat. This type of heat is still considered stored since it does not involve motion that we can see.
  • Six Kinds of Potential Energy #5 – Magnetic energy is also related to the atoms in an object. A magnet has extremely large groups of atoms lined up, in which one side of the group becomes the north pole of the magnet and the other side becomes the south pole. The magnetic field, or the space around a magnet where the magnetic force is exerted, is created by spinning and orbiting electrons. Most materials are not magnetic because the atoms’ magnetic fields do not line up. Iron atoms produce the strongest magnetic field therefore lots of magnets contain iron. Magnets are in electric motors and exert forces that affect the electrical current in wires. This led to the development of electric power, radio, and television.
  • Six Kinds of Potential Energy #6 – Elastic energy is the internal energy of a fluid or a solid that can be converted into mechanical energy to do work. A bouncing ball, a spring, a trampoline’s webbing, and a hydraulic piston all have elastic energy. The ball, spring, and trampoline all are solids that can store energy. The piston contains either compressed air or another fluid such as the brake fluid in automobile brakes that store energy.

By using common the examples above, you can easily explain the different kinds of potential energy to your children.


Lorie Moffat has 20 years of teaching experience in both public school classroom and science museum settings. Contact her about special summer online tutoring packages.
Source: http://www.homeschool-articles.com/teaching-children-about-the-six-kinds-of-potential-energy/

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How Smart Is My Child?

By Deborah L. Ruf, Ph.D.

Many parents wonder how their children compare to other children. They may have very good reasons to suspect their children are gifted (for example, their two-year-old already knows letters and numbers or their three-year-old can read an “Exit” sign), but they’re not sure if it’s unusual or not. But, information about intelligence levels can be critical, because it helps parents to understand what their children’s needs are and to provide more opportunities for their kids’ increased growth, enjoyment, and success in areas of interest

There are certain childhood behaviors — milestones — that can tell us when children are ahead of or behind others their age. Most of the charts on childhood development show the typical range of behaviors for each age group. If your child is ahead of those tables, that doesn’t necessarily mean he or she is on the fast track or slated to inspire the next Big Bang Theory. Levels of Giftedness range from those who are simply bright to those who are intellectually astonishing.

Here’s an overview of the various levels of giftedness and milestones that are common—but not necessary—to each Level. Here, also, are the numbers at each Level of Giftedness that you are likely to find in an average elementary classroom of 28 children. It is the overall “feel” of where the child fits that tells you the Level.

Level One

  • These children show interest in many things before they are even two years old – like colors, saying the numbers in order, and playing simple puzzles.
  • Most of them are good talkers by age three, and by four, many print letters and numbers, recognize simple signs, their name, and know most of alphabet.
  • By the time they are six years old, many read beginner books and type at the computer, and most read chapter books by age seven.
  • It is not unusual to find six to eight Level One children in an average classroom, children who are nearly always a few steps ahead of what the teacher is teaching the whole class.

Level Two

  • These bright children love looking at books and being read to, even turning pages without ripping them, by 15 months. Some shout out the name of familiar stores as you drive past.
  • Many of these children know lots of letters by 18 months and colors by 20 months, and between ages three and four, they count small groups of objects, print some letters and numbers, and they very likely drive their parents crazy with all their questions.
  • They’ll sit for what seems like hours as you read advanced level books, especially fiction and fantasy, to them, but they require a bit less of your time by age six, because most of them read for pleasure and information on their own by then.
  • Level Two children can find only one or two others in their classroom who are as advanced as they are, which starts to make it hard to find good friends.

Level Three

  • They’re born wide-eyed and alert, looking around the room, reacting to noises, voices, faces.
  • They know what adults are telling or asking them by six months. You say a toy, pet, or another person, and they will look for it.
  • Everything Level Two children do by 15 months, these kids do by 10 to 12 months, and they can get family members to do what they want before they are actually talking.
  • By two years, many like 35+ piece puzzles, memorize favorite books, and know the entire alphabet – in or out of order!
  • By three years old, they talk constantly, and skip count, count backwards, and do simple adding and subtracting because they like to. They love to print letters and numbers, too.
  • They ask you to start easy readers before five years, and many figure out how to multiply, divide, and do some fractions by six years.
  • Most of these children are a full two to five years beyond grade level by age six and find school too slow.
  • There are one or two Level Three children in every 100 in the average school. They are rarely in the same elementary class and can feel very, very lonely.

Level Four

  • Level Four babies love books, someone to read them, and pay attention within a few months of their birth.
  • They are ahead of Level Three children by another 2 to 5 months while less than two years old.
  • They have extensive, complex speaking by two years, and their vocabularies are huge!
  • Most of them read easy readers by 3½ to 4½ years, and then read for information and pleasure by age five, with comprehension for youth and adult level books at about 6 – 6½ years.
  • There are about one per 200 children in the average school. Without special arrangements, they can feel very different from their typical classmates.

Level Five

  • Level Fives have talents in every possible area. Everything is sooner and more intense than others Levels.
  • They have favorite TV shows before 6 – 8 months, pick out letters and numbers by 10-14 months, and enjoy shape sorters before 11 months.
  • They print letters, numbers, words, and their names between 16 – 24 months, and often use anything that is available to form these shapes and figures.
  • They show ability with 35+ piece puzzles by less than 15 months and interest in complex mazes before they are three.
  • Musical, dramatic, and artistic aptitudes usually start showing by 18 months.
  • Most speak with adult-level complexity by age two.
  • At two and three-years-old they ask about how things work, and high interests in science – particularly biological and life and death questions – emerge.
  • They understand math concepts and basic math functions before age four.
  • They can play card and board games ages 12 and up by age 3½ to 4.
  • They have high interest in pure facts, almanacs, and dictionaries by age 3½.
  • Most read any level of book by 4¼ to five years.
  • They read six or more years beyond grade level with comprehension by six years and usually hit 12th grade level by age 7 or 8.
  • We know they occur more often than once in a million and regular grade school does not work for them. Levels Three through Five score similarly on ability tests—very high.

Once you have a sense of your children’s abilities, you can provide them with more activities and experiences that build on these strengths and take advantage of their talents. Parents who have more than one child may notice that each child seems to have different interests and talents even when we encourage them equally. This is because we don’t cause our children’s abilities; we can only recognize and nurture them. To do less is truly depriving them of chances to do what they are good at and what they enjoy. To do less for our children probably chips away at their potential, too, for how can we get good at the things we don’t get to practice? There are more potential geniuses – children who are remarkably intellectually different from their same-age classmates – than most people believe, and your child may well be one of them.

This article has been reprinted with permission from the author.   Deborah Ruf, Ph.D., is a specialist on gifted children and adults for Educational Options, and President of Talent Igniter, home of the Ruf Estimates™ of Levels of Gifted, an online screening tool for parents. Her book, 5 Levels of Gifted: School Issues and Educational Options (2005) summarizes “levels of giftedness” and highlights highly to profoundly gifted children. See www.talentigniter.com.
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