500
Although the November 1959 Kilauea Iki eruption on the island of Hawaii began with a line of fountains along the wall of the crater, activity was later confined to a single vent in the crater's floor, which at one point show lava 1900 ft straight into the air (a world record). What was the lava's exit velocity in feet per second? [Hint: If Vo is the exit velocity of a particle of lava, its height T seconds later will be s=VoT-16T^2 feet. Begin by finding the tame at which ds/dT=0. Neglect air resistance.]
What is approximately 348.712 ft/s