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mcnealymt
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Energy -- Cannon Ball and Conservation of Energy
A cannon tilted up at a 30.0 angle fires a cannon ball at 80m/s from atop a 10m -high fortress wall. What is the ball's impact speed on the ground below?
Conservation of Energy
Ugi+KEi= KEf
*please note that the ground is the zero for potential energy *
Ugi+KEi= KEf
mgh+.5mVi^2= .5mVf^2 (m cancels out)
gh+ .5Vo^2= .5V1^2
V1= Square root of {(gh+.5Vo^2)/.5}
81.22m/s
Is this right? I expected the velocity to be much greater since the object was in freefall.
Homework Statement
A cannon tilted up at a 30.0 angle fires a cannon ball at 80m/s from atop a 10m -high fortress wall. What is the ball's impact speed on the ground below?
Homework Equations
Conservation of Energy
Ugi+KEi= KEf
*please note that the ground is the zero for potential energy *
The Attempt at a Solution
Ugi+KEi= KEf
mgh+.5mVi^2= .5mVf^2 (m cancels out)
gh+ .5Vo^2= .5V1^2
V1= Square root of {(gh+.5Vo^2)/.5}
81.22m/s
Is this right? I expected the velocity to be much greater since the object was in freefall.
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