physics
posted by alex .
A boy drops a stoneA, down from a cliff 480 meters high, next he throws a stoneB, 1 second later  at what initial velocity was the stoneB be thrown so as to meet the stoneA on ground at the same time? g=10 m/s2.

physics 
drwls
Require the following:
(g/2)T^2 = 480
(g/2)(T1)^2 + V*(T1) = 480
You have two equations in two unknowns (V and T) and can solve for V.
The first equation tells you that stone A requires
T = 9.8 seconds to fall to the ground. (if g= 10)
Use that value of T in the second equation to solve for V.
Respond to this Question
Similar Questions

Physics
From the edge of the rooftop of a building, a boy throws a stone at an angle 24.0° above the horizontal. The stone hits the ground 4.40 s later, 104 m away from the base of the building. (Ignore air resistance.) Find the initial velocity … 
Physics
From the edge of the rooftop of a building, a boy throws a stone at an angle 24.0° above the horizontal. The stone hits the ground 4.40 s later, 104 m away from the base of the building. (Ignore air resistance.) Find the initial velocity … 
physics
From the edge of the rooftop of a building, a boy throws a stone at an angle 30.0° above the horizontal. The stone hits the ground 4.10 s later, 112 m away from the base of the building. (Ignore air resistance.) (a) Find the initial … 
physics
A stone is dropped from a 75 m high building. when this stone has dropped 15m, a second stone is thrown downward with an initial velocity such that two stones hit the ground at the same time. find a. time taken for the first stone … 
physics
A stone is dropped from a 75 m high building. when this stone has dropped 15m, a second stone is thrown downward with an initial velocity such that two stones hit the ground at the same time. find a. time taken for the first stone … 
Physics
Help imediately please very urgent! A stone is dropped from a cliff 200m high,if a second stone is thrown vertically upwards 1.50sec after the first was released,strike the base of the cliff at the same in stant as the first stone,with … 
Physics
A stone is dropped from rest from the roof of a 100m high building; 2.00 s after that, a second stone is thrown straight down with initial speed v0, and the second stone passes the first stone 21.6 m above ground. (a) When are the … 
physics
From the edge of the rooftop of a building, a boy throws a stone at an angle 26.1° above the horizontal. The stone hits the ground 4.25 s later, 103m away from the base of the building (b) Find the initial velocity of the stone. (c) … 
physics
from a cliff of 49m high ,a man drops a stone 1s later he throes second stone . they both hit the ground at the same time . find out the speed with which he throws the second stone. 
math
a child standing at the edge of a cliff 100m high throws a stone vertically downwards. The stone hits the sea 4s later. Ignoring air resistance, find the initial speed with which the stone is thrown