ClassX Video Lessons Youtube Channel Smile and Learn English Number Pi – π – Math for Kids – What is Number Pi?
Hello friends! Today, we’re going to learn about a very special number that you can find in all circles around you: the number pi, written as π. Pi is a mathematical constant that helps us understand the relationship between the perimeter (the distance around the circle) and the diameter (the distance across the circle through its center) of a circle.
So, how does this relationship work? Imagine trying to fit the diameter of a circle into its perimeter as many times as you can. You can fit it about three times, plus a little bit more. That’s why pi is approximately equal to 3.14. We call it a constant because pi is the same for every circle, no matter how big or small. This means pi is always about 3.14.
Want to see pi in action? You can try this simple experiment at home. Grab a measuring tape and find a round object, like a bicycle wheel. Measure the perimeter of the wheel and then measure its diameter. When you divide the perimeter by the diameter, you should get a number close to 3.14.
For example, if a wheel’s perimeter is 98.8 inches and its diameter is 31.4 inches, dividing 98.8 by 31.4 gives you about 3.14.
Let’s try another example with a swimming pool. If the perimeter is 51.5 feet and the diameter is 16.4 feet, dividing 51.5 by 16.4 also gives you about 3.14.
Isn’t it amazing? No matter which circle you measure, dividing the perimeter by the diameter will always give you a number close to 3.14. This happens because pi is a mathematical constant, meaning it never changes.
Here’s something even cooler: pi is represented by the Greek letter π and is an infinite number. This means it goes on forever: 3.1415926535897932384… and so on. But in everyday life, we usually shorten it to 3.14 to make calculations easier.
Today, we discovered that pi is one of the most important numbers in math. It’s used in many fields like architecture, mechanics, and engineering. Without pi, many of the things we build and design wouldn’t be possible!
Did you enjoy learning about pi? There’s so much more to explore! Keep discovering and having fun with math!
Find a round object at home, like a jar lid or a clock. Use a string to measure the perimeter by wrapping it around the object, then measure the string with a ruler. Measure the diameter across the center. Divide the perimeter by the diameter and see how close you get to 3.14. Share your results with the class!
Create a piece of art using the digits of pi. Write out the digits of pi (3.14159…) in a spiral or other creative design on paper. Use different colors for each digit to make it visually interesting. Display your artwork in the classroom to celebrate pi!
Plan a Pi Day celebration on March 14th (3/14). Bring in circular treats like pies or cookies. Measure their perimeters and diameters, then calculate pi. Discuss why pi is important and share fun facts about pi with your classmates.
Write a short story or poem about pi. Imagine pi as a character and describe its adventures in the world of mathematics. How does pi help solve problems? Share your story with the class and illustrate it with drawings.
Go on a scavenger hunt to find circular objects in nature, like tree rings or flower centers. Measure their perimeters and diameters, then calculate pi. Take photos or draw pictures of your findings and present them to the class.
Here’s a sanitized version of the provided YouTube transcript:
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[Music]
Hello friends! Today we’d like to introduce a very famous number found in all circumferences and circles you see around you: the number pi. Pi is a mathematical constant that indicates the relationship between the perimeter and the diameter of a circumference.
But how can we describe this relationship? It’s about fitting the diameter as many times as possible into the perimeter of the circumference. Let’s look here: one, two, three, and a little bit more—that’s it! We can fit three diameters into the circumference in a small part.
That’s why we know that pi equals approximately 3.14. We say that it’s a constant because the number pi is the same for every circumference in the world. In other words, this number is always equal to 3.14.
Would you like to check that? It’s very simple! Look for a measuring tape and measure the perimeter of a round object you have at home. For example, the wheel of this bike. Divide the length of the perimeter by its diameter, and the result you’ll get will be approximately 3.14.
Let’s see: the perimeter of this wheel is 98.8 inches, and its diameter is 31.4 inches. If we divide 98.8 by 31.4, we’ll get approximately 3.14.
Now measure the perimeter of this swimming pool. Divide the length by its diameter, and you’ll also get approximately 3.14.
Let’s see: the perimeter of this circular swimming pool is 51.5 feet, and its diameter is 16.4 feet. If we divide 51.5 by 16.4, we’ll get approximately 3.14.
It’s like magic, isn’t it? The result we get every time we divide the perimeter by the diameter of any circle in the world will always be approximately 3.14. This happens because pi is a mathematical constant; in other words, it’s always the same number regardless of what the circles or circumferences may measure.
There’s a very interesting fact we haven’t told you about yet: pi is represented by this Greek letter and is an infinite number: 3.1415926535897932384… and the digits go on forever. In everyday life, this number is often shortened to 3.14 to be expressed in a simple way and to make calculations easier.
Today we learned that the number pi is one of the most important mathematical constants. Many architecture, mechanics, or engineering projects wouldn’t be possible without the number pi.
[Music]
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This version maintains the original content while ensuring clarity and readability.
Pi – A special number that represents the ratio of the circumference of a circle to its diameter, approximately equal to 3.14. – In math class, we learned that pi is used to calculate the circumference of a circle.
Circle – A round shape where all points are the same distance from the center. – We drew a circle using a compass in our geometry lesson.
Diameter – A straight line that passes through the center of a circle and connects two points on its boundary. – The diameter of the circle is twice the length of its radius.
Perimeter – The total distance around the outside of a shape. – To find the perimeter of a rectangle, you add up the lengths of all its sides.
Constant – A value that does not change. – In the formula for the area of a circle, pi is a constant.
Measure – To find the size, length, or amount of something using standard units. – We used a ruler to measure the length of the rectangle.
Number – A mathematical object used to count, measure, and label. – The number 7 is an odd number and is less than 10.
Experiment – A test or investigation, especially in science or math, to discover something unknown. – We conducted an experiment to see how changing the shape of a paper affects its ability to hold weight.
Relationship – A connection or association between two or more things. – In math, we studied the relationship between the radius and the circumference of a circle.
Math – The study of numbers, shapes, and patterns. – Math helps us solve problems and understand the world around us.
