- #1
Westin
- 87
- 0
Homework Statement
Jack and Jill are maneuvering a 3570kg boat near a dock. Initially the boat's position is [PLAIN]https://s3.lite.msu.edu/adm/jsMath/fonts/cmsy10/alpha/144/char68.png2,0,9[PLAIN]https://s3.lite.msu.edu/adm/jsMath/fonts/cmsy10/alpha/144/char69.pngm and its speed is 4.6m[PLAIN]https://s3.lite.msu.edu/adm/jsMath/fonts/cmmi10/alpha/144/char3D.pngs. As the boat moves to position [PLAIN]https://s3.lite.msu.edu/adm/jsMath/fonts/cmsy10/alpha/144/char68.png12,0,0[PLAIN]https://s3.lite.msu.edu/adm/jsMath/fonts/cmsy10/alpha/144/char69.pngm, Jack exerts a force of [PLAIN]https://s3.lite.msu.edu/adm/jsMath/fonts/cmsy10/alpha/144/char68.png-80,0,290[PLAIN]https://s3.lite.msu.edu/adm/jsMath/fonts/cmsy10/alpha/144/char69.pngN, and Jill exerts a force [PLAIN]https://s3.lite.msu.edu/adm/jsMath/fonts/cmsy10/alpha/144/char68.png0,240,0[PLAIN]https://s3.lite.msu.edu/adm/jsMath/fonts/cmsy10/alpha/144/char69.pngN.
What is the final speed of the boat?[/B]
Homework Equations
W=Fd
Kfinal = Kinitial +W
KE=(1/2)mv^2[/B]
The Attempt at a Solution
1) Final total work
Jack Work = (-80*10)+(0*0)+(290*-9) = -3410
Jill Work = 0
(It says my Work is correct)
2) Kfinal = Kinitial + W
Kinitial = (1/2)(3570)(4.6)^2 = 37770.6
Kfinal = 37770.6+(-3410)
Kfinal = 34360.6
3) Final Velocity = KE/m
34360.6/3570 = 9.6248m/s
Not sure where my error is... any help would be appreciated![/B]
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