How Far Did the Cannonball Roll?

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The discussion revolves around calculating the distance a cannonball rolled down a hill during the siege of Constantinople in 1453, given its mass and the work done by gravity. The user is seeking guidance on how to derive the distance from the work done, acknowledging the need to consider both linear and rotational kinetic energy. There is confusion regarding the appropriate formulas, particularly concerning the moment of inertia for the cannonball. The conversation highlights the importance of understanding the relationship between work, energy, and motion in solving physics problems. Ultimately, the user is looking for clarity on the correct approach to find the distance traveled.
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Homework Statement



In 1453, during the siege of Constantinople, the Turks used a cannon capable of launching a stone cannonball with a mass of 5.40 x 10^2 kg. Suppose a soldier dropped a cannonball with this mass while trying to load it into the cannon. The cannonball rolled down a hill that made an angle of 30.0° with the horizontal. If 5.30 x 10^4 J of work was done by gravity on the cannonball as it rolled down a hill, how far did it roll?

Homework Equations





The Attempt at a Solution



I know that you're looking for the distance traveled, obviously, but how do i get to that?!
KE = 1/2 mv^2?
 
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duckywucky said:

Homework Statement



In 1453, during the siege of Constantinople, the Turks used a cannon capable of launching a stone cannonball with a mass of 5.40 x 10^2 kg. Suppose a soldier dropped a cannonball with this mass while trying to load it into the cannon. The cannonball rolled down a hill that made an angle of 30.0° with the horizontal. If 5.30 x 10^4 J of work was done by gravity on the cannonball as it rolled down a hill, how far did it roll?

Homework Equations





The Attempt at a Solution



I know that you're looking for the distance traveled, obviously, but how do i get to that?!
KE = 1/2 mv^2?

The cannonball has two forms of KE. Linear KE (your formula that you listed), and rotational KE , which is influenced by the moment of inertia of the ball...
 
So what formula would i use for the inertia of the ball?
 
duckywucky said:
So what formula would i use for the inertia of the ball?

You tell us! It's your class.
 
Kindly see the attached pdf. My attempt to solve it, is in it. I'm wondering if my solution is right. My idea is this: At any point of time, the ball may be assumed to be at an incline which is at an angle of θ(kindly see both the pics in the pdf file). The value of θ will continuously change and so will the value of friction. I'm not able to figure out, why my solution is wrong, if it is wrong .
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