• C​​​
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    3 years ago

    I saw a physics question once that ended with: “For the purposes of this exercise assume the Earth is flat.”

  • PP44
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    3 years ago

    I may be taking this too seriously, but the bear should bounce all the way down along with the ball after the first bounce of the ball and the first step of the bear. When they meet, the ball is at its peak and have no energy, potential or kinetic. It cannot prevent the bear from falling with it.

    Edit : I’m so stupid. I meant that the ball has no kinetic energy but only potential, and can not give it upon contact with the bear. If you want you can still use my original formulation just by setting the “origin” potential energy at the beginning of the problem. Then you have negative potential energy when the ball drop. Inelegant in a way, but allow the energy of the ball to stay at zero, the potential energy being at any time equal to the opposite of the kinetic energy.

    • Ephera
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      3 years ago

      I mean, if we interpret that curvature as that actually being the highest point to which the ball would rise without a bear in the way, then yeah.

      To me, that curvature doesn’t look quite quadratic enough at the top, so presumably the bear threw it downwards with a bit of speed and then kicks it back down with every step. So, the ball would still have kinetic energy when it’s at the height of the bear.

      • PP44
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        3 years ago

        Oh you’re right ! It’s even clearly suggested in the second image… I really was tired when I wrote this shitty comment…

        • Ephera
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          3 years ago

          No worries, I didn’t really look at that second panel either until after I came up with that explanation.

    • xarvos
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      3 years ago

      What do you mean, the ball has highest potential energy at its peak

      • PP44
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        3 years ago

        How stupid am I ? very much so… I edit my post right away !