SOLUTION: I could do 4a. But not 4b, its hard! :o Question 4. A girl throws a ball vertically upwards with speed 8ms-1 from a window which is 6m above horizontal ground. (a) find t

Algebra ->  Vectors -> SOLUTION: I could do 4a. But not 4b, its hard! :o Question 4. A girl throws a ball vertically upwards with speed 8ms-1 from a window which is 6m above horizontal ground. (a) find t      Log On


   



Question 107897This question is from textbook Mechanics I
: I could do 4a. But not 4b, its hard! :o
Question 4.
A girl throws a ball vertically upwards with speed 8ms-1 from a window which is 6m above horizontal ground.
(a) find the greatest height above the ground reached by the ball. - completed, i got 9.3 metres which was correct.
1.5 seconds later she drops a second ball from rest out of the same window.
(b) Find the distance below the window of the point where the balls meet.
I cant do (b) can any one help? Thanks alot in advance! :D
This question is from textbook Mechanics I

Answer by scott8148(6628) About Me  (Show Source):
You can put this solution on YOUR website!
the balls meet when they are at the same height ... you can solve for the time and then find the height

(second ball height)=(first ball height) ... -.5gt^2+6=-.5g(t+1.5)^2+8(t+1.5)+6

once you find t, use h(t)=-.5gt^2+6