/97,/A ball is dropped from rest at a height 0o above the ground. At the
same instant, a second ball 1s launched with speed uvo Stralght up
from 崗e ground, at a point directly below where the other ball 1S
dropped. (a) Find acondition on u0o Such that the two balls Will col-
ide in mid-air. (b) Find an expression for the helght at Whieh they
collde.
生 名 油1 ,
