physics =(
posted by Jordan .
A person on a small, 7.00 meter high, hill aims a waterballoon slingshot straight at a friend hanging from a tree branch 4.00 meters above and 6.00 meters away. At the instant the water balloon is released at 7.00 m/s, the friend lets go and falls from the tree, hoping to avoid being hit by the water balloon. Calculate the following:
(a) the time for balloon to reach tree ______________s
(b) the height of balloon at that time ________________m
(c) the height of the falling friend at that time ___________________m
i don't even know where to begin. thanks!

Draw a picture.
It is not clear to me where the 7m hill comes in. If I interpreted it correctly, it is of no use except that it permits the water balloon and the person to fall freely below the ground!
See:
http://img689.imageshack.us/img689/5825/1260658746b.png
Let
D=horizontal distance between the two friends = 6m
V=vertical distance between the two friends = 4m
u= initial velocity of the balloon making an angle θ (theta) with the horizontal = 7 m/s
ux=horizontal component of initial velocity = ucos(θ)
uy=vertical component of initial velocity = usin(θ)
H1(t)=height above initial level of balloon at time t
= uy*t(1/2)gt²
H2(t)=height of friend measured from top of tree at time t
= 0 (1/2)gt²
1. Time to reach tree
T = D/ux
2. H1(T)=uy*T(1/2)gT²
3. H2(T)=(1/2)gT²
Note that H1 is measured from ground, and H2 is measured from top of tree, at 4 m above ground.
My calculations tell me that the balloon hits the poor friend. 
Forgot to mention:
θ=(theta) is the angle aimed directly at the friend, so
θ=arcTan(4m/6m)
Respond to this Question
Similar Questions

physics
A water balloon was dropped from a high window and struck its target 1.1 seconds later. If the balloon left the person’s hand at –5 meters/sec, what was its velocity on impact? 
physics
a boy on a small hill aims his water ballon slingshot horizontally straight horizontally at a second boy hanging from a branch of a tree at a distance of d away . at the instant ballon is released the second boy let go and fall off … 
AP Physics
A monkey is hanging from a branch located exactly 24 meters along the ground from the hunter. The monkey is 14 meters above the ground. The hunter aims directly at the monkey and fires a water balloon at the monkey just as the monkey … 
Physics
A monkey is hanging from a branch located exactly 24 meters along the ground from the hunter. The monkey is 14 meters above the ground. The hunter aims directly at the monkey and fires a water balloon at the monkey just as the monkey … 
Physics
A water balloon is thrown horizontally at a speed of 2.00 m/s from a roof of a building that is 6.00 m above ground. At the same instant the balloon is released a second balloon is thrown straight down at 2.00 m/s from the same height. … 
physics
a hotair balloon having initial velocity vi as it ascends. Then, a water balloon is dropped from the basket when it is 135 meters high and would hit the ground after 9.00 seconds. a) find the velocity of the hotair balloon upon release … 
Physics(pleaseee help!!)
You drop a water balloon on your friend’s head from the thirdstory window of your apartment building, 15.0 m from the ground. What is the water balloon’s acceleration while it is in the air? 
Physics  URGENT
A water balloon is launched at a speed of 23 m/s and an angle of 36 degrees above the horizontal. The water balloon hits a tall building located 20 m from the launch pad. At what height above the ground level will the water balloon … 
Physics
A person wants to launch a water balloon and hit the top of a tower, 50.0 meters away. The water balloon launcher is angled at 25 degrees. The water balloon leaves the launcher at 68 m/s. If the balloon hits the top of the tower, how … 
physics
A water balloon is launched at a speed of 42 m/s and an angle of 36 degrees above the horizontal. The water balloon hits a tall building located 27 m from the launch pad. At what height above the ground level will the water balloon …