Question
Sam tosses a ball horizontally off a footbridge at 3.2 m/s. How much time passes after he releases it until its speed doubles?
Answers
drwls
The vertical velocity component Vy would have to increase to sqrt3 times the initial horizontal velocity, Vx, so that V^2 = Vx^2 + Vy^2 = 4 Vx^2, and
V = 2 Vx
To achive that velocity, it must fall a distance H such that
M g H = (1/2) M Vy^2 = 3/2 M Vx^2
H = [3/(2g)]*Vx^2
V = 2 Vx
To achive that velocity, it must fall a distance H such that
M g H = (1/2) M Vy^2 = 3/2 M Vx^2
H = [3/(2g)]*Vx^2
marco
i don't understand your work. please try to explain it more thoroughly.