Education Technology

# Activities

Aust Senior

50 Minutes

• ##### Device
• TI-Nspire™ CX CAS
• ##### Software

TI-Nspire™ CAS

5.0

## Volume of a Football

#### Activity Overview

Students use calculus (solid of revolution) in both Cartesian and Parametric form to determine the volume of an ellipse when it is rotated around the axis to form an ellipsoid (football). Students also use arc-length to check measurements.

#### Objectives

The solid of revolution for an ellipse is much more straight forward than students may think. One of the most common ellipsoids is an AFL football. Sherrin, the official supplier of AFL footballs manufacture a range of different sizes. Students determine the volume of selected footballs from their website, however there is a twist, and its not a torpedo, more of a drop punt. Football sizes are provided as circumference measurements, so students need to use the arclength to generate greater accuracy.

#### Vocabulary

• Solid of revolution
• Arc length
• Relation
• Cartesian form
• Parametric form