What Voltage Does Voltmeter V1 Read in a Transformer with Tapped Secondary Coil?

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SUMMARY

The voltmeter V1 in the discussed transformer setup reads 120 V. This conclusion is based on the transformer turns ratio, where the primary coil has 200 turns and the secondary coil has 600 turns, with the tap at 200 turns. The voltage across the tapped section is calculated using the formula V_secondary = (N_secondary / N_primary) * V_primary, confirming that the voltage at the tap is indeed 120 V. The confusion regarding the 360 V reading arises from a misunderstanding of voltage potential versus current flow.

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Homework Statement



27.An alternating current power supply rated at 120 V is connected to the primary coil of a transformer. The coil has 200 turns. The secondary coil has 600 turns, and is tapped 200 turns from the top end, as shown. What is the reading on voltmeter V1?
(diagram attached)

A.
0 V
B.
40 V
C.
80 V
D.
120 V
E.
360 V


Homework Equations





The Attempt at a Solution



I don't know how to solve this but the answer sheet says D.
Would it mean that 120 volts flows east through the middle wire and west through the top?

But then what happens to the 240 volts flowing east through the bottom wire?
If it goes through V1 wouldn't it read 360v?

I would really appreciate it if someone could explain. Thank you.
 

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fchen720 said:

Homework Statement



27.An alternating current power supply rated at 120 V is connected to the primary coil of a transformer. The coil has 200 turns. The secondary coil has 600 turns, and is tapped 200 turns from the top end, as shown. What is the reading on voltmeter V1?
(diagram attached)

A.
0 V
B.
40 V
C.
80 V
D.
120 V
E.
360 V


Homework Equations





The Attempt at a Solution



I don't know how to solve this but the answer sheet says D.
Would it mean that 120 volts flows east through the middle wire and west through the top?

But then what happens to the 240 volts flowing east through the bottom wire?
If it goes through V1 wouldn't it read 360v?

I would really appreciate it if someone could explain. Thank you.

Homework Statement


Voltage is a potential --- it doesn't "flow". Think of the the voltmeters as being ideal; they draw no current when they measure the potential across their connections.

If you want to determine the direction of current flow when the taps are connected to some loads, well that is another matter.
 

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