Newspapers In Education Visit NIE online at www.sidneydailynews.com, www.troydailynews.com or www.dailycall.com
Word of the Week forceful — full of force; powerful; vigorous
Gravity Facts • Objects with mass are attracted to each other, this is known as gravity. • Gravity keeps Earth and the other planets in our solar system in orbit around the Sun. It also keeps the Moon in orbit around Earth. • Tides are caused by the rotation of the Earth and the gravitational effects of the Moon and Sun. • Because Mars has a lower gravity than Earth, a person weighing 100kg (220 pounds) on Earth would weigh only 38kg (84 pounds) on Mars. • It is thought that Isaac Newton’s theories on gravity were inspired by seeing an apple fall from a tree. • While Newton’s older law of universal gravitation is accurate in most scenarios, modern physics uses Albert Einstein’s general theory of relativity to describe gravity. • Acceleration of objects due to the gravity on Earth is around 9.8 m/s2. If you ignore air resistance (drag) then the speed of an object falling to Earth increases by around 9.8 meters per second every second. • The force of gravity 100 kilometers (62 miles) above Earth is just 3 percent less than at the Earth’s surface. • The human body can handle increased g-forces as seen in activities such as dragster races, airplane acrobatics and space training. The highest known acceleration voluntarily experienced by a human is 46.2 g by g-force pioneer John Stapp. • While formula one racing drivers may feel around 5 g’s under heavy braking, they can experience over 100 g’s if a crash causes them to decelerate extremely quickly over a very short distance. • Some roller coasters have been known to include g-forces of around 4 to 6 g. • The higher something is, the greater its gravitational potential energy. Back in the Middle Ages, weapons called trebuchets were used to take advantage of this principle, using mechanical advantage and the gravitational potential energy of a counterweight to hurl rocks and other projectiles at or over walls. In modern times we use the gravitational potential of water to create hydroelectricity.
Word Search
NIE Coordinator: Dana Wolfe / Graphic Designer: Scarlett E. Smith
Gravity
Gravity is an invisible pulling force between two objects. These two objects can be anything from a grain of rice to a planet in the solar system. Nothing can escape it. The amount of gravity that an object has depends on a few things. Once of these things is where on the planet you are. Believe it or not the amount of gravity varies from place to place on Earth. Another thing that effects the amount of gravity an object has is how big the object is. The bigger the object’s mass the more gravity it will have and the smaller the mass of the object the less gravity. The final thing that affects gravity is the distance between two objects. The closer they are the stronger the gravity will be. Why is gravity important? Gravity is very important to our everyday lives. Without Earth's gravity we would fly right off it. We'd all have to be strapped down. If you kicked a ball, it would be fly off forever. While it might be fun to try for a few minutes, we certainly couldn't live without gravity. Gravity also is important on a larger scale. It's the Sun's gravity that keeps the Earth in orbit around the Sun. Life on Earth needs the Sun's light and warmth to survive. The planets them-
selves rely on gravity when they were formed and to stay together. Who discovered gravity? The first person who dropped something heavy on their toe knew something was going on, but gravity was first mathematically described by the scientist Isaac Newton. His theory is called Newton's law of universal gravitation. Later Albert Einstein would make some improvements on this theory in his Theory of Relativity. What is weight? Weight is the force of gravity on an object. Our weight on Earth is how
much force the Earth's gravity has on us and how hard it is pulling us toward the surface. Do objects fall at the same speed? Yes, this is called the equivalence principle. Objects of different masses will fall to the Earth at the same speed. If you take two balls of different masses to the top of a building and drop them, they will hit the ground at the same time. There is actually a specific acceleration that all objects fall at called a standard gravity, or "g". It equals 9.807 m/s2.
Science Projects: Laws of Gravity and Motion SWING ON A PENDULUM Your children can discover the laws of physics when they try to swing on a pendulum at the playground. What You'll Need: • Swing set • Partner • Stopwatch How to Swing on a Pendulum: Step 1: Have your kids sit in a swing and have their partner push them gently. Time how many times they go back and forth in one minute. Make sure they don't pump the swing. Just let it go on its own.
Step 2: Their partner can use a stopwatch to time precisely one minute while your children count. Step 3: Then have your children's partner push your children as hard as possible. Again, make sure they don't pump the swing. Count how many times they go back and forth in one minute. Is it any different? Step 4: Now have them try the same experiment, but pump the swing by themselves. Does adding a force affect the frequency of the swing?
WATCH AN OUNCE LIFT A POUND It may sound like it can't happen, but have your children learn about centrifugal force and watch an ounce lift a pound. How to Watch an Ounce Lift a Pound: Step 1: Have your children thread a five-foot piece of fishing line through an empty cotton spool. At one end, they should securely fasten the 1oz object so that it can be whirled about without danger. Then have them fasten a 1-lb rock to the other end of the fishing line.
Step 2: Have your kids grip the spool so that they are also holding the string beneath it. Let the heavy rock dangle down about ten inches. Rotate the light object in a horizontal circle above their head. Step 3: When the light object is spinning around fast, your children can release their grip on the string below the spool. As they continue to spin the light object, they will see the heavy object begin to rise on the string that goes through the spool. (Make sure they use a strong line and fasten objects securely so that the objects don't fly off.)
Find the words hidden in the puzzle. The words could be straight, spiral or wiggly, starting off to the right or down.
Valentine
Card Challenge
Hey Elementary Schools!
MASS FORCE WEIGHT SUN MOON ORBITS PLANET PHASES
NEW MOON GEOSTATIONARY NAVIGATION ATTRACTION GRAVITY DISTANCE EARTH
SATELLITE TWENTYEIGHT / DAYS FULL MOON ARTIFICIAL COMMUNICATION WEATHER
Have your class make cards out of materials (preferably reused items) to give to patients at Dayton Children’s Medical Center and area nursing homes. Use your creativity to give someone a great Valentine’s Day card. Make this a class project and the class with the most cards made wins a party sponsored by Scott Family McDonalds®! The class instructor wins a prize, too! Send your cards by Feb. 10, 2013, to: Dana Wolfe, Newspapers in Education, 224 S. Market St., Troy, OH 45373.
Proud Sponsors of Newspapers In Education
Nourishing Ideas. Nourishing People. antpl
biort
Unscramble the words and bring in your answers for One form per visit. Not valid with any other offer. No cash value.Valid
usn
ulpl
eesdp
A FREE ICE CREAM CONE
at all Scott Family McDonald’s®:
Tipp City, Troy, Piqua, Sidney, Greenville, Beavercreek and Fairborn. Expires Feb. 28, 2013. Answers — Ronald Wants To Know: force, plant, orbit, sun, pull, speed
ceorf