PHYS 031 Lecture Notes - Gravitational Constant, One Direction, V Engine
Document Summary
Gravitational constant = g = 9. 8 m/s directed down toward earth surface. #1: a student standing on the ground throws a ball up at 15 m/s when his hand is two meters above the ground. How long is the ball in the air before it hits the ground: motion type: motion with constant acceleration. Acceleration = a = -g = -9. 8 m/s : initial conditions: V = 15 m/s: final conditions: y = 2 m y = 0 m. 0 = y + v t + (a) . 0 = 2 + 15t + (-9. 8)t . Step a: the fall up to the top; stop. Step b: the fall from top back to ground. y = 0 m. time t : same initial conditions h = y + v t - (g) t t = t + t . 0 = v + at t = v / g: new initial conditions.