After taking an astronomy class, you purchase an astronomical telescope that has a focal length for the objective and eyepiece respectively of 173 cm and 1.20 cm. After using the telescope several times, you decide to increase its angular magnification by replacing the eyepiece. After replacing the eyepiece, the length of the barrel must be adjusted in order to bring objects into focus. Determine the best angular magnification you can obtain, if the barrel can only be shortened by 0.51 cm from its current length.

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.