For the baseball of Prob. 2/45 thrown upward with an initial speed of 30 m/s, determine the time tu from ground to apex and the time td from apex to ground.
Data from Prob. 2/45
When the effect of aerodynamic drag is included, the y-acceleration of a baseball moving vertically upward is au = −g − kv2, while the acceleration when the ball is moving downward is ad = −g + kv2, where k is a positive constant and v is the speed in meters per second. If the ball is thrown upward at 30 m/s from essentially ground level, compute its maximum height h and its speed vƒ upon impact with the ground. Take k to be 0.006 m−1 and assume that g is constant.
