physics
posted by kelly on .
An airplane is flying horizontally with a speed of 1000 km/hr (278 m/s) when it drops a payload. The payload hits the ground 37 s later. (Neglect air drag and the curvature of the Earth. Take g = 10 m/s2.)
(a) At what altitude H is the airplane flying?

The speed of the plane does not affect the time to fall. The distance that it falls in time t (when there is no initial vertical velocity component) is
H = (g/2)*t^2
They tell you what to use for g, although it is not the right number. 
5m x 37 x 37 = 6845 meters and you should use 4.9 not 5.

H=(10m/s^2)/2 X (37)^2
H=6845m