Question

a stone fell from a height of 15 m with an initial speed 10m/s .what is maxsimum speed that the stone has ?

Answer 1

Vf^2 = (10^2) -2*g*15

Answer 2

vf^2=-200 ?
if posible that maxs speed is negativ

Answer 3

good point, should be done with Vf in the same direction as acceleration. Is initial velocity up or down?

Answer 4

up

Answer 5

i am sorry, i mean down

Answer 6

ok so Vf^2 = -(10)^2 + 2*g*15

Answer 7

down : Vf^2 = (10)^2 + 2*g*15

Answer 8

i get it...yes, the answer is 20 m/s