Posted by layan on Thursday, November 26, 2009 at 7:16pm.
A stone is dropped into a river from a bridge 41.7 m above the water. Another stone is thrown vertically down 1.87 s after the first is dropped. Both stones strike the water at the same time. What is the initial speed of the second stone?

physics  MathMate, Thursday, November 26, 2009 at 11:14pm
S=ut(1/2)gt²
S=41.7 m, u=0, g=9.8 m/s²
Solve for t.
Now
S=v0(t1.87)  (1/2)g(t1.87)²
Solve for v0.