A force is a push or a pull. A force can make an object start moving, change an object's direction, and cause the object to stop moving. Fourth grade students will investigate the force of gravity and its influence on velocity (speed). Students will also engage in an experiment showing that friction is a force that works against motion, and learn about Newton's First Law of Motion called inertia (the tendency for an object to remain at rest or resist motion). Our young physicists will participate in an activity to determine if mass influences whether an object sinks or floats (buoyant force). Erosion is a powerful force that is forever changing the landscape of the planet Earth. Fourth grade students will learn the differences among weathering, erosion, and deposition.
What You Can Do at Home
Activities
Here are two projects that will help your child understand important concepts about forces. These projects are easy, fast, and fun.
1. The pulley is an example of a simple machine. Pulleys are used in elevators, venetian blinds, and construction sites to lift heavy objects. Create a simple pulley that demonstrates how the loops of rope can greatly increase your lifting power. In addition to your child, you will need another partner. You and your partner will each hold a long stick or rod about two feet apart from one another. You will try to hold the sticks apart as your child tries to pull them together using only a long rope. Let your child experiment with weaving the rope between the sticks. If your child is unsuccessful, reveal the following trick: tie one end of the rope around one of the sticks. Then loop the rope back and forth around the two sticks. Your child’s pulling power will increase with each additional loop. After each new loop is added, have your child measure how far the free end of the rope must move to bring the sticks together. © Scott Foresman 4
2. You can use a bouncing ball to investigate potential energy andkinetic energy. Ask your child to predict under which condition the ball will bounce higher: when dropped from a height of six inches or from a height of two feet. Explain that the ball receives the energy to bounce from its potential energy. A ball that is further from the ground has more potential energy. Potential energy is converted to kinetic energy (or energy of motion) as the ball moves through the air. © Scott Foresman 4
Websites
Scholastic Studyjams: Forces and Motion - Learn how friction affects the motion of objects.
http://studyjams.scholastic.com/studyjams/jams/science/forces-and-motion/force-and-motion.htm
Scholastic Studyjams: Newton's First Law of Motion: Inertia- Learn all about Sir Isaac Newton's First Law of Motion
http://studyjams.scholastic.com/studyjams/jams/science/forces-and-motion/inertia.htm
Scholastic Studyjams: Weathering and Erosion
Weathering and erosion are forces that are changing the landscape of the Earth's surface. Watch the video to learn more about these forces.
http://studyjams.scholastic.com/studyjams/jams/science/rocks-minerals-landforms/weathering-and-erosion.htm
Suggested Reading
What’s the Big Idea, Ben Franklin? by Jean Fritz. Read about how Benjamin Franklin always found time to try out new ideas and make new discoveries.
Drag! Friction and Resistance (Time for Kids Nonfiction Readers) by Stephanie Paris. This book exposes us to all the different kinds of forces that affects are daily lives.
What You Can Do at Home
Activities
Here are two projects that will help your child understand important concepts about forces. These projects are easy, fast, and fun.
1. The pulley is an example of a simple machine. Pulleys are used in elevators, venetian blinds, and construction sites to lift heavy objects. Create a simple pulley that demonstrates how the loops of rope can greatly increase your lifting power. In addition to your child, you will need another partner. You and your partner will each hold a long stick or rod about two feet apart from one another. You will try to hold the sticks apart as your child tries to pull them together using only a long rope. Let your child experiment with weaving the rope between the sticks. If your child is unsuccessful, reveal the following trick: tie one end of the rope around one of the sticks. Then loop the rope back and forth around the two sticks. Your child’s pulling power will increase with each additional loop. After each new loop is added, have your child measure how far the free end of the rope must move to bring the sticks together. © Scott Foresman 4
2. You can use a bouncing ball to investigate potential energy andkinetic energy. Ask your child to predict under which condition the ball will bounce higher: when dropped from a height of six inches or from a height of two feet. Explain that the ball receives the energy to bounce from its potential energy. A ball that is further from the ground has more potential energy. Potential energy is converted to kinetic energy (or energy of motion) as the ball moves through the air. © Scott Foresman 4
Websites
Scholastic Studyjams: Forces and Motion - Learn how friction affects the motion of objects.
http://studyjams.scholastic.com/studyjams/jams/science/forces-and-motion/force-and-motion.htm
Scholastic Studyjams: Newton's First Law of Motion: Inertia- Learn all about Sir Isaac Newton's First Law of Motion
http://studyjams.scholastic.com/studyjams/jams/science/forces-and-motion/inertia.htm
Scholastic Studyjams: Weathering and Erosion
Weathering and erosion are forces that are changing the landscape of the Earth's surface. Watch the video to learn more about these forces.
http://studyjams.scholastic.com/studyjams/jams/science/rocks-minerals-landforms/weathering-and-erosion.htm
Suggested Reading
What’s the Big Idea, Ben Franklin? by Jean Fritz. Read about how Benjamin Franklin always found time to try out new ideas and make new discoveries.
Drag! Friction and Resistance (Time for Kids Nonfiction Readers) by Stephanie Paris. This book exposes us to all the different kinds of forces that affects are daily lives.