Curated OER
How Do You Find the Surface Area of a Sphere?
What do a basketball, a bowling ball, and a ping pong ball all have in common? They are spheres. So how do you measure the surface area of a sphere? Yes, there is a formula and all you have to do is know one measurement of the sphere to...
Curated OER
How Do You Find the Lateral and Surface Areas of a Cylinder?
There are three formulas that need to be used to solve this problem. The formula for the lateral area of a cylinder, the formula for the circular base of the cylinder, and then the formula for the surface area. It seems like quite a bit,...
Curated OER
How Do You Find the Slant Height of a Cone?
Use the Pythagorean theorem formula to find the slant height of a cone. If the height of the cone and the radius of the base are given, using the Pythagorean theorem formula will be a piece of cake. Just plug in the values given and solve.
Curated OER
What is a Sector and Central Angle?
Slice a large piece of pie or slice a small piece of pie? Whichever way you slice it, this piece of pie would be a fraction of the whole pie. This analogy corresponds with the sector of a circle being a piece of the pie. The size of the...
Curated OER
What is Circumference?
There are actually two formulas to find the circumference of a circle. One formula is based on knowing the diameter of the circle, and the other is based on knowing the radius of the circle. The instructor illustrates both formulas. She...
Curated OER
How Do You Find the Circumference of a Circle if You Know the Diameter?
There are two formulas that can be used to find the circumference of a circle. Choose the appropriate formula depending on the given value in the problem. After selecting the correct formula, solve the problem using 3.14 as an estimation...
Curated OER
What is the Formula for the Area of a Sector of a Circle?
Are you looking for the formula for the area of a sector of a circle? But what's a sector? A sector is just a fraction of the area of a circle. Follow the instructor as she illustrates and labels the different parts of a circle. She also...
Curated OER
How Do You Find the Area of a Circle if You Know the Radius?
There are basically two things you need to know to find the area of a circle. First, you need to use the correct formula. Second, you have to know the value of the radius. If you know these two things then all you have to do is plug the...
Curated OER
How Do You Find the Area of a Circle if You Know the Diameter?
Do you know the formula to find the area of a circle? Do you know the value of pi? Do you know what the relationship is between diameter and radius? Yes? Then you can solve this problem. If your scholars don't know this formula then this...
Curated OER
What is the Formula for the Area of a Circle?
Cut up a circle and make a parallelogram! What? No way! Yes way! Watch the instructor illustrate just how to cut up the circle and get that parallelogram to then get the formula for the area of a circle. It really works! Base,...
Curated OER
Circumference by Math Busters
The Math Buster goes out and demonstrates a real life example of calculating circumference by walking around the edge of a circle, and compares it to walking from the edge of the circle to the center point. It is a visual demonstration,...
Curated OER
Tangents and Circles - Geometry Help
Does watching a person do a math problem help you understand a mathematical concept? If it does then this clip will be a great help. The tutor in this clip completes a geometry problem involving tangents, circles, and the Pythagorean...
Curated OER
Radius, Chord, Diameter, and Secant
What do a secant, chord, diameter, and radius all have in common? They are all components or measurements of a circle! This clip quickly defines each of these terms using verbal, written, and diagram examples.
Khan Academy
Khan Academy: Perpendicular Radius Bisects Chord
Proof that if a radius is perpendicular to a chord then it bisects the chord. This video also appears in the Geometry: Circles strand. [6:57]
Khan Academy
Khan Academy: Geometry: Language and Notation of the Circle
Formally defines a circle and different parts of a circle. Identifies the proper notation for naming different parts of a circle. [11:12]
Sophia Learning
Sophia: Converting Between Diameter and Radius: Lesson 3
Given this lesson and either the diameter or radius of a circle, you'll be able to calculate the other measure. It is 3 of 10 in the series titled "Converting Between Diameter and Radius." [2:06]
Virtual Nerd
Virtual Nerd: What Is the Formula for the Volume of a Cone?
Tutorial explains the formula for the volume of a cone and shows how to use it in an example. [5:04]
Virtual Nerd
Virtual Nerd: What Is the Formula for the Volume of a Sphere?
In this tutorial, learn how to use a cylinder with the same dimensions to find the formula for the volume of a sphere. [4:56]
Virtual Nerd
Virtual Nerd: Find the Radius of a Circle if You Know the Circumference
Use the formula for the circumference of a circle to find the radius. This tutorial shows you how to use that formula and the given value for the circumference to find the radius. [3:43]
Virtual Nerd
Virtual Nerd: How Do You Find the Radius of a Circle if You Know the Area?
You can use the formula for the area of a circle to find the radius. This tutorial shows you how to use that formula and the given value for the area to find the radius. [3:28]
Virtual Nerd
Virtual Nerd: What Is a Degree?
Watch this tutorial to learn what a degree is and how it relates to a circle. [3:08]
Virtual Nerd
Virtual Nerd: What Is Circumference?
The circumference of a circle is the distance around that circle. Take a look at this tutorial to discover the formulas for the circumference of a circle. [4:22]
Khan Academy
Khan Academy: Geometry: Parts of a Circle
Identifies and labels basic parts of a circle: center, diameter, radius, and circumference. This video also appears in the Geometry: Circles strand. [2:01]
Khan Academy
Khan Academy: Visual Understanding of Centripetal Acceleration Formula
Visual understanding of how centripetal acceleration relates to velocity and radius