What is Pi? | Circles | Circumference | Don't Memorise

TL;DR

Pi is the ratio of a circle's circumference to its diameter, approximately 3.14, and is denoted by the Greek letter "Pi".

Transcript

What is Pi? Let's assume, we are asked to draw a circle of radius three centimeters. So we draw a circle like this. The length of this red thing will be the perimeter. And we have a special name for the perimeter of a circle. It's called the circumference. This length will be the circumference. This length will measure 18.85 centimeters. The next t... Read More

Key Insights

• 🥳 Pi is a mathematical constant representing the ratio of a circle's circumference to its diameter.
• ♓ The value of Pi is approximately 3.14 or 22/7.
• ⭕ The formula for the circumference of a circle is 2πr, where r is the radius.

Questions & Answers

Q: What is Pi?

Pi is a mathematical constant that represents the ratio of a circle's circumference to its diameter, approximately equal to 3.14.

Q: How is the value of Pi calculated?

Pi's value is derived by calculating the ratio of the circumference to the diameter for various circles. It is an irrational number and cannot be expressed precisely as a fraction.

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

The formula for the circumference of a circle is 2πr, where r is the radius. Multiplying the radius by 2π gives the total length of the circle's boundary.

Q: Why is Pi denoted by the Greek letter "Pi"?

The symbol for Pi, π, was adopted because it is the 16th letter of the Greek alphabet. It is believed to have been chosen due to its association with words like perimeter and circumference in Greek.

Summary & Key Takeaways

• Pi is the ratio of a circle's circumference to its diameter and is approximately 3.14.

• The formula for the circumference of a circle is 2πr, where r is the radius.

• Pi is represented by the Greek letter "Pi" and is derived from Greek words related to perimeter and circumference.