Have you ever heard of Sir Isaac Newton? He was a super smart scientist from England, born a long time ago in 1642. Newton was not just a scientist; he was also a mathematician, astronomer, and even a writer! Imagine having so many jobs. People thought he was really clever, and he helped us understand a lot about how the world works.
You might have heard the story about an apple falling on Newton’s head. While we’re not sure if it’s true, it helped him think about gravity. Gravity is the force that makes things fall to the ground and keeps the planets moving around the sun. Newton was the first to explain this, and he wrote a famous book in 1687 called “Mathematical Principles of Natural Philosophy.” This book inspired many people and talked about gravity, motion, and light.
Newton’s first law says that things like to keep doing what they’re already doing. If something is still, it will stay still unless something moves it. If something is moving, it will keep moving unless something stops it. This is called inertia. For example, a soccer ball won’t move until you kick it, and it will keep rolling until it hits something.
Some objects are harder to move because they have more mass. Mass is the amount of stuff inside an object. A big table has more mass than a small book, so it’s harder to move. Friction is another force that can slow things down. It’s like when you try to slide a couch on a fluffy rug; it’s harder than sliding it on a smooth floor.
Newton’s second law is all about how force, mass, and acceleration work together. The law says that force equals mass times acceleration, or F = ma. Force is when you push or pull something. Mass is how much stuff is in an object, like a balloon or a bowling ball. Acceleration is how fast something speeds up or slows down.
Think about sledding down a hill. As you go down, you speed up—that’s acceleration. If you roll a bowling ball and a soccer ball down the hill, the bowling ball will go faster because it has more mass. It also takes more force to stop it.
Newton’s third law says that for every action, there is an equal and opposite reaction. This means if you push on something, it pushes back with the same force. For example, when you jump on a diving board, it pushes you back up. If a boxer punches a bag, the bag pushes back with the same force.
Imagine a cannon shooting a cannonball. When the cannonball goes forward, the cannon moves backward. This is the reaction to the action of shooting the cannonball.
We see Newton’s laws in action every day. Whether you’re playing sports, riding a bike, or just walking, these laws are at work. They help us understand how things move and interact with each other.
Thanks for learning about Newton’s laws of motion! Keep exploring and discovering the amazing world of science around you.
Inertia Experiment: Find a small toy car and a piece of cardboard. Place the toy car on the cardboard and gently push the cardboard forward. Observe how the car moves with the cardboard. Now, quickly stop the cardboard and watch what happens to the car. Discuss with a friend or family member why the car keeps moving even when the cardboard stops. This activity helps you see Newton’s first law of motion in action!
Force and Mass Challenge: Gather a few objects of different sizes and weights, like a tennis ball, a small book, and a stuffed animal. Try pushing each object with the same amount of force and observe how far they move. Which object was the hardest to move? Why do you think that is? This activity will help you understand Newton’s second law of motion and how mass affects movement.
Action-Reaction Game: Pair up with a friend or family member and play a simple game of catch. As you throw the ball, think about how your hand pushes the ball forward and how the ball pushes back on your hand. Discuss how this relates to Newton’s third law of motion. You can also try jumping on a trampoline and feel how it pushes you back up as you jump down.
**Sanitized Transcript:**
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Newton’s laws of motion. Have you heard of Sir Isaac Newton? He was an amazing scientist from England, born way back in 1642. During his 85-year life, he became known as a natural philosopher, scientist, mathematician, astronomer, religious scholar, author, and much more. That’s a lot of different jobs! Can you imagine today if you told someone you were a doctor, a scientist, a teacher, an astronaut, a psychologist, and a writer? That’s a lot of jobs for one person to have. We would probably think someone like that was very smart. Well, Isaac Newton was.
When Sir Isaac Newton lived, not a lot was known about the way the world works. Subjects like physics and math were not yet taught, so people’s understanding of how objects moved around was very limited. But then people began to make huge and important discoveries in science, math, and other subjects. We now call this time the scientific revolution, and because Isaac Newton made a lot of discoveries himself, we often call him the father of modern science.
You may think you’ve never heard of Mr. Newton, but maybe you’ve heard the story about the man who fell asleep under an apple tree and an apple fell off and hit him in the head. Sound familiar? Well, that man was Sir Isaac Newton. We aren’t sure if the story of the apple tree is true or not, but it’s said that that’s when Newton discovered gravity. He was the first to use gravity to explain the way the planets move, why the tides of the ocean occur, and other events that happen all around us.
In 1687, Newton published a book called “Mathematical Principles of Natural Philosophy.” That book inspired a lot of people. In it, he talks about gravity, how things move, math, light, and sight. Isaac Newton really loved to learn and study how things work. He was good at it too—so good that we study things he taught us, like his three laws of motion. These three laws have been tested and proven over and over for hundreds of years, so you can bet they’re pretty solid.
Let’s find out why Newton’s first law says that an object in motion tends to stay in motion while an object at rest tends to stay at rest unless acted on by some force. So what does that mean? Well, the first part of this law means a pair of snow skis aren’t going to go anywhere without a skier in them forcing them to move, or a soccer ball is going to remain in the same place on a field until someone kicks it. The other part of Newton’s law means that the skis and the soccer ball are going to keep moving until they are stopped by someone or something.
All objects tend to continue doing what they are doing—moving or staying still. Most objects will remain at rest or a standstill. Look at a book or a table; this is inertia, or a tendency to do nothing or to remain unchanged. But not all objects are the same. Bigger and heavier objects have more inertia, which requires more force to move them. In other words, a more massive object like a table has a greater tendency to resist changes in its state of motion than a book does. It’s harder to move a table than a book sitting on that table.
A moving object, like a ball rolling along a level surface, will eventually slow down and stop due to friction. Friction is also a force; it is the resistance that one surface or an object encounters when moving against another. For example, trying to push a couch that’s sitting on a fluffy rug is harder than pushing that same couch on a smooth floor. That’s because there is more friction or resistance caused by the rug than the smooth floor. Air resistance is another force that affects moving objects. If you’ve ever tried to walk outside on a very windy day, you’ll discover it’s harder to move with the wind blowing in your face. A sailboat uses air resistance to maneuver the boat by catching wind in its sails.
Once an object begins to move, its speed, or how fast it’s moving, can be measured. If the object’s speed stays the same, it has a constant speed. So whether an object is moving or staying the same, it can’t change what it’s doing unless something forces it to. For Newton’s second law, he came up with an important equation: it says that force equals mass times acceleration, or F = ma.
Let’s talk about each of those words and how they work together. When you apply force to something, it means that you try to move it or stop it from moving. To put it simply, you can either throw a football to move it or you can catch a football to stop it. Can you think of some things that you frequently move or stop from moving? How about a swing or a car? What about a door when you open or shut it?
Let’s talk about mass. Mass is the amount of stuff that makes up something. Everything has mass, from a pen to a pillow, and a pickle to a person. However, mass is different from item to item. You’re going to have far more mass than a pickle. But what about two things that are about the same size? Can they have different amounts of mass? If you said yes, you’re right! Can you think of two things that are about the same size but their weights are very different? How about a balloon and a bowling ball? The balloon is full of air, making it very light, while a bowling ball is filled with resin or graphite, making it very heavy.
This is important to know because the more mass something has, the harder it is to move it or stop it. Imagine trying to stop a soccer ball at the bottom of a hill it just rolled down. Now imagine if it were a bowling ball. Mass matters. Acceleration means a change in speed or direction of something. Have you ever gone sledding at the top of a large hill? After you take off, do you notice it doesn’t take long before you start speeding up? That’s acceleration. It’s the same thing with the bowling ball and the soccer ball rolling down a hill. Because the bowling ball has more mass, it’s going to roll faster because of the speed of acceleration, and the mass of the bowling ball means it will take more force to stop it at the bottom.
That’s how force, mass, and acceleration work together. How cool is that? Newton’s second law also talks about unbalanced forces. That means when you throw a football, the football is moving quicker than the air around it. That’s because the force is stronger than the air resistance, gravity, and friction. Eventually, gravity will stop it.
Finally, Newton realized that no matter what the mass of an object and the force applied, the acceleration will always be in the same direction as the force. So when you decide to slide down a large hill, make sure you’re up for it because once you go down, there’s no coming back up.
Newton’s third law says that for every action, there is an equal and opposite reaction. Whatever force you give to something, it will give that same force back to you. Jumping on a diving board is an example of Newton’s third law. As you exert force on the diving board by jumping, in return, the diving board pushes back on you with the same amount of force you gave it. If a boxer punches a punching bag with 10 pounds of force, in return, his fist is going to receive 10 pounds of force. The forces will always be equal, just opposite.
Let’s watch this cannonball being shot out of a cannon. Did you notice that the cannon moved backward when the cannonball was shot forward? That backward movement is the cannon’s reaction to the action of shooting the cannonball forward. They are opposite movements but equal forces. Friction is a reaction force, or something that holds back something else that is moving forward. Remember the rug and the couch?
You may not have realized it, but you and I are part of Newton’s laws every day. You might even say we put them in motion. Thanks for watching! Be sure to subscribe for more educational resources. Click the link below.
