A rock is thrown vertically upward with an initial speed of 100 ft/s. At the same instant another rock is thrown vertically downward from the top of a 280 ft cliff with an initial speed of 40 ft/s. Neglecting air friction,

Question

anonymous · Answer

Lol....wat we have to find here....is it the time when they both Will meet ryt ?

anonymous · Answer

yea the time and position!

anonymous · Answer

so how then we can find the time?

anonymous · Answer

V = Vu - ( -Vd)   = 100 + 40 = 140ft/s

anonymous · Answer

V = d/t

t = d/t

 t = 280 / 140 = 2s