Ignore all the information for a moment. Just think, what things do you need to know to find the answer?
Once you know what you're looking for, then you can try to use all the information in the problem to find whatever it is you need to know.
I was thinking projectile motion but then I ignored that. I think I would need the force exerted by the ball on the canon and vice versa and then apply it. Is this correct?
Okay, try to find this from the given information.
I suggest working backwards. What would you like to know about the state of the canon just after the shot has been fired?
Yomo710. Did you delete the original post? Please do not do that! Now nobody can make sense of the thread.
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