(Answered, thanks yall) Basically I have three competing understandings: potential energy with respect to height is linear AND gravity is constant in force applied per time (right?) AND at the end of falls you are losing height faster because greater speed.
So with these three things being my understanding I don’t understand how at the end of a fall (some arbitrary speed) you can lose more height and thus PE per second but be accelerated at the same force. I don’t see how you could expend more PE but not be putting in more energy to acceleration… Where does that extra PE lost by higher speed go? Does it take more energy to accelerate when moving faster? It shouldn’t I think ignoring fancy energy momentum stuff that doesn’t apply at 10 mph lol.
So yeah, I don’t get it. I’d be very grateful is someone could solve this for me. I know I must be missing something but don’t know what. This is a question i’ve argued with my brother about a little and tried to look up a few times but the forum posts I’ve found aren’t exactly my issue I think. I also tried asking some ai and it didn’t see my problem I think. For the record I’m in school for chemistry so not a lay person per se but not well read at all either.
In: Physics
Energy is the potential to do work. Work can be defined as a FORCE over a distance. If you exert a force of 5 pounds (lbf) on an object and move it 5 feet, you have done (5×5=) 25 ft-lbf of work. So the only two factors in how much potential energy is stored in an object at some height are: force and distance. Distance is jsut the height, sot hats easy. But what do we do with the force term? WEll, how much force is the object exerting? Well, luckily we have Newtons Law to help us out, which states the F=ma (Force – mass * acceleration). So we cna figure out the force exerted on the objectg from gravity if we know its mass, and we know the acceleration due to gravity. So now we know that we can figure out the potential energy if we know the mass of the object, its height above the datum, and the acceleration due to gravity! Gool thing is, gravity is a constant (assuming youre staying on/near the surface of teh earth), the “a” doesn;t really change if youre at 1 ft or 1,000 ft of elevation.
POut all that together, and you can see that the only things that determine an object potential energy are its mass, its height above the datum, and the acceleration due to gravity. Nothing to do with its speed. If its at rest at 1,000 ft, or moving 50 ft/s downward at 1,000 ft, it has the same potential energy in that instant. If its at 50 feet, it will have another amount, regardless of its velocity. The only factors that come into play are mass, acceleration, and height. And since mass and acceleration dont change during a fall, the only variable that influences PE is the height. And since height scales linearly with height, that means the PE will scale linearly with height.
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