Does current flow from point A to ground in electrical circuits?

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Current does not flow from point A to ground in the discussed circuit, as the ground node is primarily a reference point indicating zero electrical potential rather than a physical connection to the Earth. In practical applications, grounding can help mitigate unwanted signals such as 50Hz hum or radio frequency interference, but the specific components in the circuit do not draw current to ground. The concept of a ground is essential for calculations in simulation software like SPICE, which requires a ground node for its operations. Circuit designers categorize grounds into various types, such as signal return, analog ground, and digital ground, to manage different current types and minimize noise. Ultimately, while the idea of a zero-voltage ground is useful, it remains an approximation due to inherent resistance and inductance in real-world conductors.
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Is there any current flows from point A to the ground (see the attachment)?

We use ground node to idicate somewhere in the circuit has ZERO electrical potential. Do we really connect that point to the ground in real world or we just mark that point to make it easier to do calculations?
 

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    ground node.PNG
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Your second post...Ethanoic.

There is no current to ground for the components shown. In practice, there can be signal sources that are not shown, they are incidental and usually unwelcome. Example: 50Hz hum induced in that wiring due to proximity to mains wiring, or radio frequencies inducted by nearly or distant stations, or passing taxis with 2-way radios, or motors or car ignitions, or computer chip signals, etc., etc. The Earth connection can divert these and render them inconsequential to the operation of your circuit.

The Earth connection may be shared by other circuits, not shown here, but possibly partnering it in some way. It represents a piece of wire, not a connection to terra firma, usually. :smile: Often it's a connection to an area of copper on a circuit board.
 
NascentOxygen said:
There is no current to ground for the components shown.

Are we looking at the same diagram? It looks like a DC current of Vbattey/R would be flowing through the resistor. What am I missing?
 
In the real world and for this circuit this point - GND - is not needed. SPICE requires a GND node - that is where it starts all of it's calculations from.
 
The idea of having a surface or conductor with 0 volts (ground) at all points is a useful concept, but in reality, it's best an approximation.
All practical conductors suffer from resistance and inductance. Thus if current flows between any two points on a conductor, there will be a corresponding voltage drop.
For this reason, circuit designers separate grounds into different categories:
* Signal return - For remote instruments or microphones
* Analog ground - For low current small signal regions
* Digital ground - Used for micro-controllers and digital circuitry (which tend to have high frequency currents)
* Power ground - Used to carry high di/dt currents within the power supply regions
* Chassis ground - Used for safety and as a place to tie down high frequency currents.
* Safety ground (or neutral) - Used with chassis ground as a means of routing dangerous currents away from users.

I may not have been complete or given the best description on some of these, but they are the common ones I think about. There's also a slew of work on how you interconnect grounds, and how you deal with noise / offset related issues...
 
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