Finding Voltage and Resistance in a Series Circuit

AI Thread Summary
To find the voltage at the end of a series circuit with an initial voltage of 15V, the total resistance of the resistors must be calculated, which is 100.05Kohm. The current flowing through the circuit is determined to be 14.9mA. In a series circuit, the voltage does not remain static; instead, it drops across each resistor based on their resistance values. To find the voltage at a specific point, measure the voltage drop across the resistor of interest and use Ohm's law to calculate the resistance. Understanding these principles is crucial for accurately determining voltage and resistance in series circuits.
tamz273
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Homework Statement


I need to find the VOLTAGE at the end of a series of resistors, where the initial voltage is 15V


Homework Equations


R = R1+R2+R3
I = V/R


The Attempt at a Solution


Total resistance = 100.05Kohm (R1+R2+R3)
I @ Va = 15/100.05 = 14.9mA

Now I don't know how to find the RESISTANCE at the end of the circuit (point Va)

Any help? I am not HORRIBLE with circuits, but isn't voltage static in a series circuit? and current changes? So shouldn't the Voltage be the same at the beginning and end of the series of resistors?! :S
 
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Actually, in a series circuit, all components carry the same current.
 
so how would i calculate the voltage at a certain point in the circuit?
 
tamz273 said:

Homework Statement


I need to find the VOLTAGE at the end of a series of resistors, where the initial voltage is 15V


Homework Equations


R = R1+R2+R3
I = V/R


The Attempt at a Solution


Total resistance = 100.05Kohm (R1+R2+R3)
I @ Va = 15/100.05 = 14.9mA

Now I don't know how to find the RESISTANCE at the end of the circuit (point Va)

Any help? I am not HORRIBLE with circuits, but isn't voltage static in a series circuit? and current changes? So shouldn't the Voltage be the same at the beginning and end of the series of resistors?! :S

15 volts / 100.05 ohms = .1499 amperes (which is 149.9 mA)

Since you know the current (correct current is .1499 amperes) flowing through ALL the series resistors, merely measuring the voltage drop across the resistor in question, then divide that voltage drop by your current of .1499 amperes and it will yield the resistance value of that resistor in ohms.
 
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