Radius Teacher Resources

Find Radius educational ideas and activities

Showing 61 - 80 of 2,430 resources
A circle is a set of all the points that are equal distance from a center point. Learn the definition of some of the terms that are associated with a circle: diameter, radius, chord.
Students investigate the properties of circles. In this geometry instructional activity, students calculate the area and perimeter of a triangle. They identify the perimeter and radius length of a circle.
The teacher diagrams and explains the different terms of what comprises a sphere. Follow along and learn about the: radius, diameter, great circle, center, and hemisphere.
The formula for the volume of a sphere is volume equals four-thirds pi times the radius cubed. That's a mouth-full. But if you are given the radius value of the sphere, all you have to do is plug it in and do the arithmetic. Just remember to use the order of operations.
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 is a good way to introduce them to all the variables in the formula.
The formula to find the volume of a cone is volume equals one-third times the base times the height. The base can be found by using the formula to find the area of a circle: base equals pi times radius squared. So it seems that the area of the base needs to be found to solve for the area of a cone. Follow along in this video as the instructor goes through the steps for finding the area of a cone.
What is the formula to find the volume of a cylinder? Here's the formula - volume equals base times height, and the base of a cylinder is base equals pi times radius squared. If the is a given value for radius, and a given value for height, then the volume of the given cylinder can be found.
Bring your math class around with this task. Learners simply identify parts of a given circle, compute its radius, and estimate the circumference and area. It is a strong scaffolding exercise in preparation for applying the formulas for the area and circumference of circles.
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, circumference, height, radius, pi, put these all together to find the formula of the area of a circle.
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 plugs in the known values and solves each equation to show how they come up with the same solution.
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.
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 calculate the surface area. So if you are given the value of the radius then you can plug it into the formula and find the surface area.
In this finding the radius of circles worksheet, students must calculate the radius of 4 circles. Students are given diameter and must write the radius on the line for each circle. 
Using Cabri Jr. students construct a circle and determine the equation of the circle they drew by finding the center and the radius. Students use the distance formula to derive the equation of their circle.
Learner use three random locations on the coordinate system and simplify the expression and assign result to the variable loc. They substitute guesses for the center and radius of the circle in the equation for the center of a circle and plot the result and solve for the radius, and the coordinates of the center.
The equator and longitudinal lines make interesting circles to study in terms of arc length. Using Google Earth or a globe, pupils research specific questions about size and distance. This a great activity to bring some real-world application into your classroom. 
In this area, surface area, and volume worksheet, students solve 19 short answer problems. Students find the area of two dimensional polygons and circles. Students find the surface area and volume of prisms and pyramids.
Tenth graders solve and complete 14 different geometry problems. First, they find the area and circumference of a circle with a given radius. Then, they find the area between a circle and an inscribed equilateral triangle given the measurement of each side. Pupils find the sum of the areas of the shaded regions in figures shown.
For this recognizing round and round worksheet, 6th graders use the diameter or radius of circular objects and distance traveled to find the circumferences and revolutions and use this information to solve word problems. Students solve six word problems.
Geometry whizzes solve and complete 24 different problems that include determining the volume and surface area of spheres and cones. First, they use the given information to determine the volume of a cone. Then, pupils use the given information to determine the surface area of a sphere.

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