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I was doing a problem in the TPR book today, and now I'm kind of confused about the conservation of momentum law.
So, momentum is conserved in both elastic and inelastic collisions. But, the TPR book says dropping an object to the ground is NOT a case where momentum is conserved.
But, I feel like momentum IS conserved for falling objects. If the object is falling towards the earth, isnt it true that the earth is also technically "falling" towards the object, due to the mutual gravitational attraction? which means that when the object is falling towards the earth with some speed v at some point in time, the earth is also moving toward the object with a certain speed as well (although its infinitesmally small). Considering the gigantic mass of the earth and its tiny velocity, isnt it possible that the momentum of the object is equal and opposite to the momentum of the earth (m1v1 = m2v2), so that the collision is still inelastic and momentum is conserved?
Maybe I'm just not seeing something. Could someone explain please?
So, momentum is conserved in both elastic and inelastic collisions. But, the TPR book says dropping an object to the ground is NOT a case where momentum is conserved.
But, I feel like momentum IS conserved for falling objects. If the object is falling towards the earth, isnt it true that the earth is also technically "falling" towards the object, due to the mutual gravitational attraction? which means that when the object is falling towards the earth with some speed v at some point in time, the earth is also moving toward the object with a certain speed as well (although its infinitesmally small). Considering the gigantic mass of the earth and its tiny velocity, isnt it possible that the momentum of the object is equal and opposite to the momentum of the earth (m1v1 = m2v2), so that the collision is still inelastic and momentum is conserved?
Maybe I'm just not seeing something. Could someone explain please?