If a jewish person were to accidentally turn on the light in their bedroom, or if the television were accidentally turned on (for these purposes, let's assume that the person in question woke up, temporarily forgot what day it was, and turned on the electrical appliance), would the jew be allowed to benefit from the new situation (e.g. they can now read in their bedroom, or watch the single channel on TV). Leaving aside if someone else were to see the jewish person using this new situation (for this question, the person is living in an apartment, so nobody can look in and see what he's doing in his bedroom or living room), are there any halachic ramifications for benefiting from the new situation? Or must the jew simply 'ignore' the new situation and act like it doesn't exist?
As a side question, would it matter if the electrical appliance were turned on by a non-jew or a minor? I know a few times a shul had no lights on, and had to use a non-jew to turn on the lights as a 'loophole' to get the lights on; would they also be able to benefit from this?