Consider a diagram The peak of the trajectory occurs at time t1 . This is the point where the ball reaches its maximum height ymax . At the peak the ball switches from moving up to moving down, even as it continues to travel horizontally at a constant rate.of the ball at time t0 .(Figure 2) Recall that t0 refers to the instant just after the ball has been launched, so it is still at ground level ( x0=y0=0m ). However, it is already moving with initial velocity v 0 , whose magnitude is v0=30.0m/s and direction is =60.0degrees counterclockwise from the positive x direction