Author Topic: Resistors question  (Read 1629 times)

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Offline 10101Topic starter

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Resistors question
« on: August 02, 2015, 04:35:00 pm »
I need help finding the voltage in the voltmeter please (image below).
Could you please explain how to solve it ?
Thanks in advance  :-+
 

Offline IanB

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Re: Resistors question
« Reply #1 on: August 02, 2015, 04:43:09 pm »
Find any node or nodes in the circuit where the voltage is not already stated. Label these unknown voltages with names, such as V1. Now use Ohm's law to write equations relating the unknown voltage(s), the resistance values, and the currents through those resistors. Do a current balance (all currents into and out of a junction must sum to zero). Solve the resulting equations for the unknown voltage(s).
 

Offline PSR B1257

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Re: Resistors question
« Reply #2 on: August 02, 2015, 04:53:38 pm »
Quote
Could you please explain how to solve i
Apart of the explanations above, it's just a voltage divider. The resistor across the supply is irrelevant, if you have an ideal source (i.e. no internal series resistance) 
In theory, there is no difference between theory and practice. But, in practice, there is.
 

Offline 10101Topic starter

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Re: Resistors question
« Reply #3 on: August 02, 2015, 05:00:35 pm »
Thx to both  :-+
my doubt was the 2nd parallel resistor added to the voltage divider  |O ,but since it's irrelevant, great !
 

Offline TheElectricChicken

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Re: Resistors question
« Reply #4 on: August 11, 2015, 06:58:59 pm »
true, it is a trick resistor. So to finish your homework, if the supply reads 86volts then the meter reads 11v
 


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