1. If a ball dropped from a person's hand, and it then undergoes a free fall. The acceleration is 9.81m/s^2, if it undergoes a uniform acceleration, can i use the formula, d=Vt to find the distance it travels? or if it relates to the gravity, i must only use the formula with a, for instance, like d=Vit+at^2/2. 2. If a rocket is launched with a certain speed, does it also have acceleration when it takes off? My teacher said when this rocket goes up, the speed is decelerating due to gravity, so meanwhile when it is still approaching upward, does it still have the acceleration same as the beginning? So the speed is increasing? Then, how come it slows down? Must this acceleration greater than 9.81? Thanks for explaining.