Energy is the strongest force in the universe. But where did it come from? This program covers the origins of energy, energy through the ages, physical and chemical changes, and the definition of energy. We'll also explore energy in different forms, including fire and its discovery, calorific energy, the invention of machines, petroleum, windmills, photosynthesis, the Sun, energy reserves, and mechanical, electrical, and luminous energies.

Originally released by Cerebellum Corporation, 2013. Streaming video file encoded with permission for digital streaming by Infobase on July 10, 2018.

What Is Energy? (1:21); --Energy (1:48); -- Transformation of Energy (2:08); -- Energy Sources (2:28); -- Energy Reserves (1:00); -- Summary (2:41); -- Credits: What Is Energy? (0:41);.