An object is falling straight down. The minimum number of axes required in a frame of reference used to analyze its motion is

For general projectile motion, when the projectile is at the highest point of its trajectory, its acceleration is zero? a)the horizontal and vertical components of its velocity are zero. b) its velocity is perpendicular to the acceleration. c)the horizontal component of its velocity is zero. d)its velocity and acceleration are both zero.

An object moves from position +34m to the position -15m in 15 seconds. what is the total displacement? what is the total velocity?

Where is the potential energy throughout the loading, cocking, and releasing of the trebuchet?