Lesson Plan #27 http://www.phy6.org/stargaze/Lnewt2nd.htm . A short section, recapitulating earlier ideas of force and inertia (also known as mass). It summarizes Newton's laws, defines the unit of force known as "Newton," and gives as a practical application of the second law the acceleration of the German V-2 rocket, used in World War II. ... This lesson plan supplements: "Newon's Second Law," section #18 . ... Mass . ... An unthinking application of Newton's second law would give . ...