Visit Your Local PBS Station PBS Home PBS Home Programs A-Z TV Schedules Watch Video Donate Shop PBS Search PBS

NOVA Online (click here for NOVA home)
Secrets of Lost Empires

Lever an Obelisk

screen shot of Lever intro screen

Your goal is to raise the tip of the obelisk three feet and to support it using as few blocks as possible.

You can locate the fulcrum at one of three points: It is now in the middle location. The mechanical advantage of the lever with the fulcrum here is 1:1. If moved to the left position, the mechanical advantage is 1:3; if moved to the right, 3:1.

Think about where you'd want the fulcrum, then figure out how many blocks you would need to achieve the goal.

By the way, the most efficient builders need a combination of only seven total weights and support blocks.

Next: the answer...


How Big Were They? | Cutting Granite with Sand | NOVA Raises an Obelisk
Lever an Obelisk | Explore Ancient Egypt | Mysteries of the Nile | Resources | Transcript

Medieval Siege | Pharaoh's Obelisk | Easter Island | Roman Bath | China Bridge | Site Map

Editor's Picks | Previous Sites | Join Us/E-mail | TV/Web Schedule
About NOVA | Teachers | Site Map | Shop | Jobs | Search | To print
PBS Online | NOVA Online | WGBH

© | Updated November 2000

Support provided by

For new content
visit the redesigned
NOVA site