Situation: one circuit is out. We have not added any new appliances, etc., but the breaker is flipped. When I flip it to make the circuit, it immediately flips again. My thoughts: there was no change to the demands placed on the circuit, therefore the breaker is worn out? I won't be bothering to anything until tomorrow, but a trip to the hardware store is in my future. Does my theory sound reasonable?
I'm not an electrician but I am an electronics tech. First thing I would do is make sure nothing in that circuit (assuming your circuit breakers are labelled accurately) is plugged in. Then turn on the circuit breaker. Gradually plug or turn on everything in that circuit one at a time until the breaker opens/trips. Now you found the "bad guy" that's tripping it. Option B is leaving everything plugged in (and of course the breaker trips) but unplug things until it doesn't trip. The first way is the safest way. Trust me you don't want option C, it's a "do not try this at home" thing best left to professionals.
Yes that's why breakers trip. They detect an increase in current (which increases as resistance "the load" decreases) and open the circuit.
What the others have said. Either a short or a worn breaker. You happen to know how old the breaker is?
Yep, short circuit in one of the wall switches. I got home to a house full of people telling me about all these things that weren't working. I checked the circuit breaker, then conducted the plug test that Oldfella recommended (option B). No luck. Only then, does one of my kids disclose that everything went out when he turned off a light, and that there was a flash, and a piece breaking off. So the toggle switch snapped, and evidently in so doing put enough extra pull on the wires to loosen the connection. Easy fix, and much better than my initial assessment.
Awesome! Glad you found the bad guy. That's what I like about analog versus digital when it comes to anything electronic or electrical. You can see, feel, smell, measure, and test alanog all day long.