Cadet Competition Written Practice Exam

Who developed the first rocket engine?

1. Newton

2. Hero

3. Galileo

4. Karman

The correct answer is: Hero

The first rocket engine is attributed to Hero of Alexandria, who lived in the first century AD. Hero is notable for his invention of the aeolipile, which is often considered an early form of a steam engine and works on a principle similar to that of a rocket engine. The aeolipile used steam pressure to produce rotary motion, demonstrating the basic concept of thrust which is foundational for rocket propulsion. This innovation by Hero laid the groundwork for future developments in propulsion technology, although it was not used for practical applications in the way modern rocketry is. By comparison, figures like Newton contributed to the understanding of physics and motion that would later be crucial in rocketry, and Karman was involved in aerospace dynamics but did not invent a rocket engine. Galileo made significant contributions to the scientific method and mechanics but did not design a rocket engine either. Therefore, the choice of Hero as the developer of the first rocket engine acknowledges his pioneering work in the principles of propulsion.