Connected to the wall: it’s AC (alternating current). half the wave is already negative. You can rectify it backwards, apparently. Or, you can use a split phase transformer.
Connected to a really big battery: big inverter just swaps the leads on the battery really fast.
Hold in your hand: negative charge pump. Magic & momentum.
Depends on relative to what.
Connected to the wall: it’s AC (alternating current). half the wave is already negative. You can rectify it backwards, apparently. Or, you can use a split phase transformer.
Connected to a really big battery: big inverter just swaps the leads on the battery really fast.
Hold in your hand: negative charge pump. Magic & momentum.