Area and Volume: Finding the Area of a Circle
This clip explains that, to find the area of a circle, "
we multiply pi (approximately 3.14) by the radius squared. The clip also includes practical problems, one of which includes the circle's diameter but not its radius.
Perimeter: Circles: Circumference, Radius and Diameter
This clip explores the perimeter of circles. "The distance around a circle is called its circumference," the clip explains. "One way to find the circumference of a circle is to know its diameter." The clip then talks about the use of pi ("
the valu...
Angles, Arcs and Sectors: Angles, Circles and Sectors
This clip looks at the sector, a fraction of a circle's area formed by a central angle and its arc. "We can find the area of a sector," the clips explains, "
by multiplying the ratio of the central angle to the circle by the area of the circle."
Angles, Arcs and Sectors: Angles, Circles and Arcs
This clip includes several practical problems in its discussion of angles in circles. It also explains how to find the length of an arc.