I have been doing research and the explanations don’t make sense. Kinetic energy is based off of velocity, and so is momentum. If the kinetic energy decreases, the momentum would also have to decrease, because the objects in the collision have less energy and therefore move at slower rate, and therefore have less momentum. It seems like momentum and energy are one, but but in reality it isn’t? And here’s my thought experiment:
Two objects collide and lock together. They maintain their original momentum, but are now locked together as one. According to what I am currently learning, they have lost kinetic energy, but they have maintained their total momentum. Now, the locked objects hit an equal copy of themselves in front of them, except the copies are unlocked. Due to conservation of momentum, the locked object stops, and the copies are now at the same point the two objects were at the start of the experiment, before they collided. How can energy be lost, and then gained? Where did they go? If someone could simply explain what I’m missing, that would be very helpful as I have a test in 12 hours. Thanks!!
In: Physics
Simply, kinetic energy isn’t generally conserved, momentum is.
Total energy is conserved (as long as we’re not invoking nuclear reactions or relativity), total momentum is conserved, but there’s no particular reason to think kinetic energy by itself would be conserved.
In your thought experiment it’s too open to be sure, but one of your assumptions about an intermediate state isn’t right.
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