Why is it that we use voltages and watts more often than amperages? 9v batteries, 12v car battery, 1000W Microwave oven. But amperages not so much, even though its “half” of what makes power, A*V=W. What property of amperes makes it so “unnecessary” to be aware of?
Bonus: how many amps and volts does a typical 1000W microwave use?
Because current (amps) has nothing to do with energy. Formally, an ampere is the current of 1019 electrons moving through a given point in 1.6 seconds; in more reasonable terms, it’s 1 coulomb per second. The amount of energy in those electrons doesn’t matter to the amount of current, but energy is very relevant to making machines do things.
Potential (volts) does include energy; specifically, 1 volt is 1 joule per coulomb. Add more energy and you get more volts, but the current remains the same. So volts are more relevant to how much use you can get out of your electrons.
Power (watts), meanwhile, tells you how effective your machine is at extracting that energy. 1 watt is 1 joule per second. Suppose you are running a 6W heater. Every second, that heater converts 6J of electrical energy into heat energy, while the current remains the same.
Thus, knowing current is important for electrical engineering, but potential and power matter more for operation.
“power is only related to voltage” is nonsense. Current and voltage contribute equally to power (P=IVpf, but I am not going to discuss power factor here).
The reason current is less frequently mentioned is that our electric power system supplies power (current and voltage) to many users and the wiring for giving power to many locations is simpler and more reliable when we try to keep voltage relatively constant and let the power using devices demand just as much current as they need to extract the power they need. This means current values can vary wildly between circuits, so it is not very informative to talk about current unless you know a lot about what is hooked up and consuming power nearby. The circuit that supplies the lights uses much less current than the one that supplies the air conditioner (when it is on) but there are often many lights on a single circuit so the current is quite different in different segments of wire even while the voltage only varies a but in each circuit.
You could devise a wiring system that held current constant by running the current in a loop through all the consuming devices, but like Christmas tree lights if any load disconnected then all the loads would stop receiving power, which would make it very unreliable.