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# A.C. circuit question watch

1. Ok, ac circuits are not in my syllabus, but I found this in an old Past Paper (of 1995), so JUST IN CASE the impossible happens, can someone please explain this to me.

A mains circuit contains six similar bulbs connected in series. One of the bulbs has a broken filament. Voltmeter X and Y of infinite resistance are placed in the circuit as shown.

What are the voltmeter readings in Volts?

X Y
A 0 0
B 0 240
C 40 40
D 240 0

Actually, it seems a bit interesting.
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2. Its a potential divider. Most PD across most resistance. (Ac is irrelevant)

A broken filament has an infinite resistance so gets all the PD

Answer is 240v for X. 0v for Y
3. Oh Thanks

Good thing I did not simply ignore it.

My teacher said that no current flows so the no voltmeter would show any reading, but you are correct, I checked the answer in a solved paper.

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