Obama helps bust myths

US President Barack Obama is appearing on Mythbusters, a television series that uses science to separate fact from fiction.

Obama's appearance on the popular Discovery Channel show is part of a White House effort to highlight the importance of science, maths and engineering as experts warn that low interest in these subjects among United States students could hurt the economy.

The Obama episode, to air on December 8, reprises an earlier debunking of the 2000-year-old story that Greek mathematician and engineer Archimedes set fire to an invading Roman fleet using a system of mirrors to focus the sun's rays.