- #1

Josh chips

- 7

- 0

- Homework Statement
- A stone is dropped from a point 320 meters above the ground; at the same instant another stone is thrown upward from a point 100 meters below the first. I f the two stones strike the ground simultaneously, what is the initial velocity of the second stone.

- Relevant Equations
- y=ut +1/2at^2

since the question states they hit the ground at the same time i firs find the time they hit the ground

y= ut + 1/2at^2 initial velocity is 0 for the first stone

320= 0 + 4.9t^2 this

t= 8 secs

since the 2nd stone was thrown 100 m below stone 1

distance from ground is 220m

220 = ut - 1/2at^2

220= 8u- 4.9*8^2

this give initial velocity as 66.7 m/s but am not sure if its the correct answer need some help

y= ut + 1/2at^2 initial velocity is 0 for the first stone

320= 0 + 4.9t^2 this

t= 8 secs

since the 2nd stone was thrown 100 m below stone 1

distance from ground is 220m

220 = ut - 1/2at^2

220= 8u- 4.9*8^2

this give initial velocity as 66.7 m/s but am not sure if its the correct answer need some help