Question: I always see voltmeters connected in parallel with a component, but what happens if you connect it in series? I think it's due to the high resistance of a voltmeter but I don't *really* see why this would be a problem: It just means that the current going through the circuit is shifted down a level, but all things remain the same right? (Sorry if this is wrong, I just started learning circuits.)

Thanks

Note: I already saw [this](https://physics.stackexchange.com/questions/143204/why-are-ammeters-used-in-series-and-voltmeters-in-parallel) but I didn't understand the explanations there.

Answer: 
> 
> I think it's due to the high resistance of a voltmeter but I don't really see why this would be a problem: It just means that the current going through the circuit is shifted down a level, but all things remain the same right?
> 
> 
> 

Ideally, a voltmeter should have such a high resistance that it's equivalent to an open circuit. 

This means that when connected to some device in series, essentially no current will flow through it, and no current will reach the device being tested. Usually that means the device won't operate in a normal way.
@Jdeep - the voltmeter should read close to the output potential of the cell/battery, assuming the other components in the circuit have a total resistance that is significantly smaller than that of the voltmeter (which is the case a lot of the time, given the large typical resistance of a voltmeter).