Hello, I wanted to ask a few questions regarding magnets and batteries, and EM induction. First off, could I use batteries to replace a low voltage dc power supply, like say 2 V or so by connecting the ends of the battery in series to a circuit? As an extension, could I connect two batteries in series to obtain double the voltage? Is it ok to use two batteries in series with different voltage ratings, like say, an AAA and an AA? If I could, what would be the voltage I could obtain from one battery? As in, say I use one AA battery, which is rated as 1.5 V. Do I obtain a full 1.5 V with one battery, or is it 0.75 V? Another question is whether I could power an electromagnet with a voltage way lower than what is indicated. I have a 230 -255 rated ac-V magnet, which I got by halving and removing the upper half of a microwave transformer. I replaced the primary coil in it. It looks like this: Could I power it with a voltage in the range of 2-10 V dc? What would be the effect on its magnetic field? Would it be strong enough to induce a current in the mA range? Also, with such an electromagnet, what is the relationship between the current and the magnetic field strength? Finally, suppose I use an electromagnet to induce a current in a loop of wire. How could I connect a voltmeter to measure the induced emf? In series with the circuit, or in parallel to the circuit? Thanks for answering the questions. I know there are a lot.