While standing on top of a 323 m tall building, you see Iron Man flying straight down toward the ground at a speed of 35.0 m/s. Just as he passes you, you drop a can of Dr Pepper off the roof. How fast is the can going when it passes Iron Man?

Answer 1

time to intercept:

323-35.0t = 323-4.9t^2
t = 7.14

http://www.wolframalpha.com/input/?i=323-35.0t+%3D+323-4.9t^2

Now, knowing that the can has speed

v = -9.8t

figure it out.

Answer 2

i need more help

Answer 3

what, you can't plug in t=7.14 into

-9.8t?

Answer 4

i did its giving me the wrong answer

Answer 5

well, if -69.972 is not right, then there may be an error in the answer key.

Did you try 69.972, since it just asks for speed, not velocity?

I can't see where I did anything wrong. Maybe someone else can spot a mistake.