38. dr. john paul stapp was a u. s. air force officer who studied the effects of extreme acceleration on the human body. on december 10, 1954, stapp rode a rocket sled, accelerating from rest to a top speed of 282 m/s (1015 km/h) in 5.00 s and was brought jarringly back to rest in only 1.40 s. calculate his (a) acceleration in his direction of motion and (b) acceleration opposite to his direction of motion. express each in multiples of g (9.80 m/s2) by taking its ratio to the acceleration of gravity.

At a certain instant after jumping from the airplane a, a skydiver b is in the position shown and has reached a terminal (constant) speed vb = 52 m/s. the airplane has the same constant speed va = 52 m/s, and after a period of level flight is just beginning to follow the circular path shown of radius ρa = 2330 m. (a) determine the velocity and acceleration of the airplane relative to the skydiver. (b) determine the time rate of change of the speed vr of the airplane and the radius of curvature ρr of its path, both as observed by the nonrotating skydiver.