# What is the Circumference of a Circle? | Perimeter of a Circle | Don't Memorise | Summary and Q&A

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December 20, 2014
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Infinity Learn NEET
What is the Circumference of a Circle? | Perimeter of a Circle | Don't Memorise

## TL;DR

Pi is a special constant that represents the ratio of the circumference to the diameter of a circle, and it is approximately equal to 3.14 or 22/7.

## Key Insights

• 🥳 Pi is a constant that represents the ratio of a circle's circumference to its diameter.
• ♓ Pi is approximately equal to 3.14 or 22/7.
• ♓ The circumference of a circle can be calculated by multiplying the diameter by Pi or using the formula 2PiR.
• 🏑 Pi is a fundamental constant in mathematics with various applications in different fields.
• ♓ The value of Pi is consistent for all circles, regardless of their size or radius.
• ♓ The approximate value of Pi as 3.14 is commonly used for most calculations.
• 😑 Pi is an irrational number, meaning it cannot be expressed as a simple fraction.

## Transcript

Here's a very interesting question. What is Pi? Assume we draw a circle of radius three centimeters. It will look something like this. As we know this red boundary of the circle will be its perimeter. We have a special name for the perimeter of a circle. It's called the circumference of the circle. But how do we measure the circumference of the cir... Read More

### Q: What is Pi?

Pi is a mathematical constant that represents the ratio of a circle's circumference to its diameter. It is denoted by the Greek letter "π" and is approximately equal to 3.14 or 22/7.

### Q: How is the circumference of a circle calculated using Pi?

The circumference of a circle is found by multiplying the diameter of the circle by Pi. Alternatively, it can be calculated using the formula 2PiR, where R is the radius of the circle.

### Q: Is Pi the same for all circles?

Yes, Pi is a constant value that is the same for all circles. It does not depend on the size or radius of the circle.

### Q: Why is Pi considered an important constant in mathematics?

Pi is a fundamental constant in mathematics because it appears in various formulas and calculations involving circles and curves. It has numerous applications in geometry, trigonometry, calculus, and physics.

## Summary & Key Takeaways

• Pi is the ratio of a circle's circumference to its diameter, and it is constant for all circles.

• The circumference of a circle can be calculated by multiplying Pi by the diameter or by using the formula 2PiR, where R is the radius.

• Pi is approximately equal to 3.14 or 22/7, and it is a fundamental constant in mathematics.