Circumference

Circumference

Wilfredo Rodriguez

Multimedia Project #4

Circumference

What is a circle?

• A circle is defined as a set of points equidistant from a given point.

Circumference

What is a radius?

• The radius of a circle is a segment that has an endpoint on the center and another on an endpoint on the circle.

Circumference

What is the diameter?

• A diameter is a straight line through the center and terminating in both directions on the circumference.

Circumference

What is the circumference?

• The circumference of a circle is the distance around the circle. You can think of it as the perimeter of a circle (periphery).

Circumference

The circumference

of a circle

Circumference

How do we find the circumference?

• For all circles of all sizes the formula

• C = circumference, d = diameter,

and r = radius.€

C = 2πr......,or,......C = πd

Circumference

First we need to find (pi)!

Is it…..

3.1415926535897932384626433832795028841971693993751058209749445923078164062862089986280348253421170679821480865132823066470938446095505822172535…..?

What is ?

Circumference

How do we find π?

• π is found through the ratio of the circumference and the diameter. π is always approximately 3.14.

€

C

d≈ 3.14,...or......,

C

d≈ π

Circumference

The number of times you must travel along the diameter of the circle to go the same distance as all the way round the circle is known as Pi.

oncetwice

Since is a bit more than 3.

three times acrossand a little

bit more!

Circumference

Summary

Circumference

= × Diameter

Circumference

Student Activities

• GeoGebra Demonstration

• Student Activity 1

• Student Activity 2

• Student Activity 3

• Student Activity 4

• Archimedes