in 1865 jules verne proposed sending men to the moon by fi ring a space capsule from a 220-m-long cannon with fi nal speed of 10.97 km/s. what would have been the unrealistically large acceleration experienced by the space travelers during their launch? (a human can stand an acceleration of 15g for a short time.) compare your answer with the free-fall acceleration, 9.80 m/s2.