To explain the cause of the Space Shuttle Challenger disaster in 1986, Richard Feynman played show-and-tell.
The Nobel Prize-winning physicist was speaking in front of a presidential commission that was investigating the explosion. The hearing in Washington, D.C., was televised, so the public could also watch his presentation.
Using a cup of cold water, he demonstrated how a part of the shuttle—the rubber O-ring—could malfunction. Immersing the O-ring material in water, Feynman enabled his audience to see that the insulation around the rubber part would lose its elasticity as the temperature fell to 32 degrees (the reading on the day of the Challenger launch).
Feynman followed two rules that public speakers use when employing props as educational tools: keep it simple and don’t demonstrate more than the audience wants to know.
To enliven your presentation, consider what type of prop might spark a group’s curiosity.
Danny Day, an entrepreneur, followed these guidelines when addressing potential investors at a conference. Seeking to demonstrate his new firm’s commitment to quality assurance for chemicals bought online, he hoisted two five-gallon drums on stage.
He told the audience that the drums contained two different grades of titanium oxide: one worth $100,000 (high-quality pharmaceutical grade) and the other worth $220 (industrial grade).
“From where you’re sitting, like buyers on the Internet, how would you know the difference?” he asked.
He concluded by showing that his company would empower consumers to identify the higher-quality material.
— Adapted from “Try Show and Tell to Make the Audience Really Understand,” Joey Asher, www.speechworks.net.