13-Year-Old Wins Science Fair with 'Death Ray' Experiment. Sort of... (cnn.com) 83
There is no archaeological evidence that the contraption existed, as Sener noted in his paper, but many have tried to recreate the mechanism to see if the ancient invention could be feasible. In Sener's attempt at the ray, he set up a heating lamp facing four small concave mirrors, each tilted to direct light at a piece of cardboard with an X marked at the focal point. In this project he designed for the 2023 Matthews Hall Annual Science Fair, Sener hypothesized that as the mirrors focused light energy onto the cardboard, the temperature of the target would increase with each mirror added.
In his experiment, Sener conducted three trials with two different light bulb wattages, 50 watts and 100 watts. Each additional mirror increased the temperature notably, he found... The temperature of the cardboard with just the heating lamp and the 100-watt light bulb and no mirrors was about 81 degrees Fahrenheit (27.2 degrees Celsius). After waiting for the cardboard to cool, Sener added one mirror and retested. The focal point's temperature increased to almost 95 F (34.9 C), he found. The greatest increase occurred with the addition of the fourth mirror. The temperature with three mirrors aimed at the target was almost 110 F (43.4 C), but the addition of a fourth mirror increased the temperature by about 18 F (10 C) to 128 F (53.5 C)...
Sener was not attempting to light anything on fire, as "a heating lamp does not generate anywhere near enough heat as the sun would," he said. But he believes that with the use of the sun's rays and a larger mirror, "the temperature would increase even more drastically and at a faster rate" and "would easily cause combustion."
The powerful weapon wouldn't work on cloudy days, Sener's paper points out, and even a moving ship might diminish its impact.
But in an interview with CNN, Sener calls Archimedes' death ray "a neat idea".