A boy wishes to make a catapults out of
a rubber band of width 9mm and thickness 1.55mm. Determine the length of the band
he must use so that when the stretches it by 0.25
of its natural length and releases it, the velocity of the pebble of mass 0.0006kg is
30ms - Take the youngs modulus of the rubber
to be 4x10000000nm-2

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.