physics
posted by prabhat
a stone is thrown in such a manner that it would just hit a bird at the top of a tree and afterwards reach a maximum height double that of the tree . if at the moment of throwing the stone the bird flies away horizontally with constant velocity and the stone hits the bird after some time . the ratio of horizontal velocity of stone to that of the bird is 1¡n+1¡¡Ìn?

Damon
Well, to make it easy, let's say the tree is 50 meters high. Then the max stone height will be 100 meters.
That gives us a vertical problem to solve.
What is Vi, initial vertical velocity?
(1/2) m Vi^2 = m g h
so
Vi = sqrt(2 g h = sqrt (200*9.81) = 44.3 m/s
so when will it get to the tree top?
h = Vi t  4.9 t^2
50 = 44.3 t  4.9 t^2
4.9 t^2 44 t + 50 = 0
t = [ 44 +/ sqrt(1936 980) ] /9.81
t = [ 44 +/ 30.9 ] /9.81
t = 1.34 seconds on the way up, WHERE IT WOULD HAVE HIT THE BIRD
t = 7.64 seconds on the way down  WHEN IT HITS THE BIRD!
the bird flew for 7.64 seconds at speed u so went 7.64 u meters from the tree
The stone went at horizontal speed s so went a total of 7.64 s meters
of which 1.34 s was the distance from the thrower to the tree. so (7.641.34) s = 7.64 u
I guess you can find s/u now :)
Respond to this Question
Similar Questions

math
A man 1.7m tall observe a bird on top of a tree at angle of elevation of 40degree. If the bird distance between the man's head and the bird is 25m, what is the height of the tree? 
Physics
From the top of a cliff with 80 m height a stone is thrown vertically and finally hit the surface of ocean. Initial velocity of stone is 40 m/s. Find: (a) time to reach to max height. (b) how high goes from surface of ocean? 
physics
A stone thrown vertically upwards from the top of a building takes 3s to reach its maximum height . Find 1. The velocity with which it is thrown 2.the maximum height it reaches above the builibg 
MATH
A TREE AND A FLAGPOLE ARE IN THE SAME GROUND.A BIRD ON TOP OF THE TREE OBSERVERS THE TOP AND BOTTOM OF THE FLAGPOLE BELOW IT AT ANGLES OF 46 AND 60 DEGREES RESPECTIVELY. IF THE TREE IS 10.65m HIGH WHAT IS THE HEIGHT OF THE FLAGPOLE 
MATHEMATICS
A TREE AND A FLAGPOLE ARE IN THE SAME GROUND.A BIRD ON TOP OF THE TREE OBSERVES THE TOP AND BOTTOM OF THE FLAGPOLE BELOW IT AT ANGLES OF 45 AND 60 DEGREES RESPECTIVELY. IF THE TREE IS 10.65m HIGH WHAT IS THE HEIGHT OF THE FLAGPOLE? 
English
1. The bird fell into the tree. 2. The bird fell in the tree. 3. The bird fell out of the tree. 4. The bird fell from the tree. 5. The bird fell off the tree.  Are they all grammatical? 
physics
a stone is thrown vertically upward an initial velocity of 12m/s from the top of a building . it takes 3.4s for the stone to hit the ground a. find the height of the building b. find the maximum height that the stone will reach c. … 
Physics
A stone thrown upward to just reach the top of a palm tree that is 8.2m tall. Calculate the initial speed that is require 
PHYSICS
A stone thrown from the top of a building is given an initial velocity of 40.0 m/s straight upward. The building is 70.0m high, and the stone just misses the edge of the roof on its way down, determine (A) The time at which the stone … 
SCIENCE
A stone thrown from the top of a building is given an initial velocity of 40.0 m/s straight upward. The building is 70.0m high, and the stone just misses the edge of the roof on its way down, determine (A) The time at which the stone …