- #1
rpullo
- 15
- 0
Homework Statement
Little Willy, clumsy clot,
From window sill dislodged a pot.
He shouts below to Little Milly:
"Step aside, it'll knock you silly!"
The window sill is 35.0 m above the sidewalk where Millly is standing directly below the falling pot. Milly is 1.05 m tall, her ears are 5.00 cm below the top of her head, and she needs 0.400 s to respond to the warning. The speed of sound in air is 340 m/s. What is the minimum height of the pot above the ground at the instant Willy shots his warning if Milly is to avoid being "potted"? Answer in m.
Homework Equations
v =d/t
d = (v1)t + 0.5a(t^2)
The Attempt at a Solution
So I first found the time is takes for the sound to reach Milly's ears:
t = d/v
t = (35.0m - 1.0m)/(340m/s)
t = 0.10 s
So the time it takes Milly to receive the warning and respond:
0.10 s + 0.400 s = 0.50 s
I use d = (v1)t + 0.5a(t^2) to find the distance the pot falls:
d = (v1)t + 0.5a(t^2) ...where v1 is 0
d = 0.5(-9.8)(0.50)^2
d = 1.225 m
I'm not sure what to do next or if I even started this question correctly. All input is appreciated!