posted by maha .
Consider a marble moving on a horizontal track with a speed of 10 meters per second( ignore friction and air resistance). the marble leaves the track and falls through the air to the ground a vertical distance of 1.5 meters.
how long does it take to for the marble to hit the ground?
you can ignore the horizontal speed of the marble (unless you want to find out far far it travels).
s = 1/2 at^2
1.5 = 1/2 * 9.8 t^2
t = 0.55 sec