So what exactly is an EMP?

So today Rhea and I discussed what an EMP was. Or at least we tried to figure out what it was. We've been trying to figure out ways to bring attention to the object and give an explanation for why it would be making noise. So I said to maybe have a subtle mention at the start of the film from the mother saying that the power company is doing EMP tests in the area so there might be power outages. An EMP is an electromagnetic pulse, and I pretty much learned about it from comic books and movies. But right now we were trying to find out if that's even scientifically accurate and if that would make sense.  A part of me was just saying, eh it'll be fine, but the inner scientist was saying to make it 100% accurate. Like even Finding Nemo was almost 100% scientifically accurate (minus the wacky adventure) but the marine biology aspect of it was. I'll keep you updated as to what we will be changing and adjusting.