is of high impedance (I hope I use correct terminology)
Impedance and resistance* are measured in Ohms. They both "resist" or "impede" the flow of current...
[u]Ohm's Law[/u] says the higher the resistance (or impedance) the lower the current. And, the higher the voltage the higher the current.
The impedance of an oscilloscope is so high that we can ignore it and assume (pretend) it's infinite. If the 'scope were the only load on the battery, we wouldn't ignore it because the battery will last longer on shelf with nothing connected than it will with a 'scope connected.
But, we usually don't talk about the resistance or impedance of the entire op-amp circuit because it can change with conditions. An op-amp with no signal will draw a certain amount of current but if we have headphones connected we are going to draw more current with a signal when the volume is turned-up.
- Resistance is one component of impedance. Inductive reactance and capacitive reactance, are the other components. In a circuit such as yours where there is no inductance or capacitance we can use the terms interchangeably. But, in AC amplifier circuits (such as yours) we usually say impedance.