AC source in parallel with resistor problem


For an AC source of for example +-12 V, can a connected resistor at any instant, have 24 V across it?

Because my textbook has a problem in it involving such a source and says (hint: consider the source as a 24 V battery)and I am trying to make sense of why this is valid.

Edit: no there is nothing at all. Just a source connected in parallel to a resistor and it's asking me to calculate the minimum resistor value if the resistor is valued at 0.25 W. The source provides a voltage of +-12 V and to calculate the resistance you would have to take the source as being equivalent to a 24 V source (according to book) then (24^2)/0.25=Minimum resistor value.

I just don't understand why you can take the value as 24 V.

Best Answer

Just a guess but this question may be referring to a split supply e.g. from a centre tapped secondary of a transformer. It is very difficult to give a definitive answer to questions without the full background.

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