Tag: #lawsofmotion#newton

Once upon a time there was a little girl named Nikki, who was a curious and adventurous girl who loved to explore the world around her.
While  learning about gravity, she was very fascinated by the story of “Newton and falling apple”.

Do you remember…she had got an amazing time machine? In order to meet Newton, the Scientist, Nikki went back in time using her time machine. She met Newton and found him very smart and who knew a lot about how things move and why. He agreed to teach Nikki some interesting facts and rules about motion that he called his laws.

One day, Nikki and Newton decided to go to the park and play with some toys. They brought a ball, a skateboard, a kite and a rocket. They had a lot of fun trying different things with their toys and learning from Newton.

The first thing they did was to roll the ball on the ground. Nikki gave the ball a gentle push and watched it roll away. Newton asked, “Do you know why the ball keeps moving after you push it?” Nikki shook her head. Newton explained, “That’s because of my first law of motion. It says that an object at rest stays at rest, and an object in motion stays in motion, unless acted upon by an unbalanced force.”

Nikki thought for a moment and asked, “What is an unbalanced force?” Newton said, “An unbalanced force is something that changes the speed or direction of an object. For example, when you push the ball, you are applying an unbalanced force that makes it move faster. But when the ball rolls on the ground, it slows down because of another unbalanced force called friction. Friction is a force that opposes the motion of an object. It happens when two surfaces rub against each other, like the ball and the ground.”

Nikki nodded and said, “Yes I remember that if there was no friction, the ball would keep rolling forever.” Newton said, “Yes, that’s right. In fact, in outer space, where there is no air or friction, objects can keep moving forever unless they hit something or are pulled by gravity.” Nikki said, “Wow, that’s amazing!”

The next thing they did was to ride the skateboard. Nikki stood on the skateboard and pushed herself forward with one foot. She felt the wind in her hair and enjoyed the speed. Newton said, “Do you know why you can move faster or slower on the skateboard?” Nikki said, “I guess it depends on how hard I push myself.” Newton said, “That’s correct. And that’s because of my second law of motion. It says that the acceleration of an object is proportional to the net force acting on it and inversely proportional to its mass.”

Nikki frowned and said, “That sounds complicated.” Newton said, “Don’t worry, it’s not as hard as it sounds. Acceleration means how quickly an object changes its speed or direction. Net force means the total amount of force acting on an object from all directions. Mass means how much matter an object has or how heavy it is. So what my second law means is that if you want to make something move faster or slower, you have to apply more or less force to it. And if something is heavier or lighter, it will be harder or easier to make it move faster or slower.”

Nikki said, “Oh, I get it now. So if I want to go faster on the skateboard, I have to push harder with my foot. And if I want to stop, I have to apply a force in the opposite direction, like dragging my foot on the ground.” Newton said, “Exactly. And if you were riding a bicycle instead of a skateboard, it would be easier to go faster because a bicycle has less mass than a skateboard.” Nikki said, “That makes sense.”

The last thing they did was to fly the kite and launch the rocket. Nia held the kite string and ran with the wind until the kite lifted off the ground and soared high in the sky. She felt a tug on the string as the kite pulled her along. Newton said, “Do you know why the kite flies?” Nikki said, “I think it’s because of the wind.” Newton said, “That’s partly true. The wind provides an upward force that lifts the kite up. But there is also another force that keeps the kite from flying away. Can you guess what it is?” Nikki looked at the string and said, “Is it the tension in the string?”

Newton said, “Yes, that’s right. The tension in the string provides a downward force that balances out the upward force from the wind. This creates a stable equilibrium where the kite stays at a constant height.”

Nikki said, “I see. So if I let go of the string, the kite will fly away?” Newton said, “Yes, it will. And if you pull on the string too hard, the kite will come down.” Nikki said, “I understand.”

Then they switched to the rocket. Nikki pressed a button and watched the rocket shoot up into the air with a loud whoosh. She saw a trail of smoke and fire coming out of the rocket’s tail. Newton said, “Do you know why the rocket flies?” Nikki said, “I think it’s because of the fire.” Newton said, “That’s partly true. The fire provides a thrust force that pushes the rocket up. But there is also another force that pushes the rocket down. Can you guess what it is?” Nikki said, “Is it gravity?” Newton said, “Yes, that’s right. Gravity is a force that attracts every object to the center of the earth. It pulls everything down, including the rocket. So the rocket has to overcome gravity to fly up.”

Nikki said, “I see. So if the rocket runs out of fuel, it will fall down?” Newton said, “Yes, it will. And if the rocket has more fuel, it will fly higher.” Nia said, “I understand.”

Newton smiled and said, “You’re very smart, Nikki. You’ve learned a lot today. Do you know what else you’ve learned?” Nikki said, “What?” Newton said, “You’ve learned my third law of motion. It says that for every action, there is an equal and opposite reaction.”

Nikki thought for a moment and said, “Is that like when I push the ball, the ball pushes me back?” Newton said, “Yes, that’s exactly right. When you apply a force to an object, the object applies an equal and opposite force to you. That’s why you feel a recoil when you launch the rocket or a tug when you fly the kite. The forces are always balanced in pairs.”

Nikki said, “Oh, I get it now. That’s very cool.” Newton said, “I’m glad you think so. You’ve just learned the basics of physics, which is the science of motion and forces. There are many more things to discover and explore in this wonderful world of ours.” Nikki said, “Thank you for teaching me, Newton. You’re the best friend ever.” Newton said, “You’re very welcome, Nikki. And thank you for being my friend too.”

They hugged each other and promised to meet once in a while, whenever Nikki needed to learn more about Science. Thereafter, Nikki returned back to her time using the time machine.

Nikki was feeling very proud of meeting Newton in person and learning  “Laws of Motion ” directly from Newton.