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]
Take a look at this tutorial to learn about circles and see the different parts of a circle. [3:54]
This tutorial provides an introduction to the term sector and gives you examples of sectors. [2:23]
Take a look at this tutorial to see how to turn a parallelogram into a rectangle to find the formula for the area. [4:46]
Learn how to use sines to find the area of a triangle. [5:33]
Tutorial explains the formula for the volume of a cone and shows how to use it in an example. [5:04]
Watch this tutorial to learn about the formula for the volume of a cylinder which is the same as the formula for the area of a circle. [5:33]
Challenged with a hypothetical engineering work situation in which they need to figure out the volume and surface area of a nuclear power plant’s cooling tower (a hyperbolic shape), students learn to calculate the volume of complex solids that can be classified as solids of revolution or solids with known cross sections. These objects of complex shape defy standard procedures to compute volumes. Even calculus techniques depend on the ability to perform multiple measurements of the objects or find functional descriptions of their edges. During both guided and independent practice, students use (free GeoGebra) geometry software, a photograph of the object, a known dimension of it, a spreadsheet application and integral calculus techniques to calculate the volume of complex shape solids within a margin of error of less than 5%—an approach that can be used to compute the volumes of big or small objects. This activity is suitable for the end of the second semester of AP Calculus classes, serving as a major grade for the last six-week period, with students’ project results presentation grades used as the second semester final test.
Practice finding the volume of rectangular prisms that have fractional side lengths. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.
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Students apply their knowledge of scale and geometry to design wearables that would help people in their daily lives, perhaps for medical reasons or convenience. Like engineers, student teams follow the steps of the design process, to research the wearable technology field (watching online videos and conducting online research), brainstorm a need that supports some aspect of human life, imagine their own unique designs, and then sketch prototypes (using Paint®). They compare the drawn prototype size to its intended real-life, manufactured size, determining estimated length and width dimensions, determining the scale factor, and the resulting difference in areas. After considering real-world safety concerns relevant to wearables (news article) and getting preliminary user feedback (peer critique), they adjust their drawn designs for improvement. To conclude, they recap their work in short class presentations.
In this video [26:45], students discover why honeybees make such great engineers by studying the underlying mathematics and design of their beehives.