- #1
Ascendant0
- 132
- 29
I understand based on the equation F = ma that if there is no acceleration, the forces on the object all balance out to 0 in all directions.
What I don't get is for example, slowly lowering a heavy stone slab at a constant velocity v, and raising it way above my head as high as I can at a constant velocity v, would be considered to be the same force (since my force on it would be equal to the normal force since there's no acceleration). Obviously, it's going to be a LOT harder raising that stone slab overhead as it would be slowly lowering it. It would take a lot more effort, yet according to the force equation, I'm still applying the same force. That to me is a bit confusing.
I'm thinking I'm just viewing "force" conceptually wrong here, but if someone could help me make more sense of why this is the case in the above example, I'd greatly appreciate it.
What I don't get is for example, slowly lowering a heavy stone slab at a constant velocity v, and raising it way above my head as high as I can at a constant velocity v, would be considered to be the same force (since my force on it would be equal to the normal force since there's no acceleration). Obviously, it's going to be a LOT harder raising that stone slab overhead as it would be slowly lowering it. It would take a lot more effort, yet according to the force equation, I'm still applying the same force. That to me is a bit confusing.
I'm thinking I'm just viewing "force" conceptually wrong here, but if someone could help me make more sense of why this is the case in the above example, I'd greatly appreciate it.