A voltmeter must always be connected in parallel right? But when I have a transformer's secondary coil which is connected in series to it, then why is there a voltmeter reading? If i connect a battery in series with a voltmeter, the voltmeter reading will be the voltage of the battery right? So are these thought arrangements correct? A secondary coil and a battery are similar that they produce an emf. When I attach a voltmeter in series then due to the high resistance, only a small current will flow through it. As a result of that small current the voltage across it will be read from that voltage. So I make use of this property when connecting it in parallel across a bulb (for example) cos voltage in a parallel circuit is the same so despite the small current there will still be that little current to insisted the voltage reading? Then, since voltage in a parallel circuit is the same, then why when I have a short circuit there will be no voltage across the shorted part of a circuit meaning a bulb is connected to a battery and a wire is placed in parallel to the bulb. I don't quite understand it. Thanks for the help!