What is the potential difference across the parallel resistors in a circuit?

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The discussion revolves around calculating the potential difference across parallel resistors in a circuit. The user initially struggles with determining the voltage at the negative terminal of the battery and calculates the total resistance and current correctly. They find the voltage across a 10-ohm resistor to be 9V, leading to a voltage of 27V across the parallel resistors. Clarification is provided that the left side of the 10-ohm resistor is at +9V, while the negative terminal of the battery is at -27V. The conversation concludes with the user expressing understanding of the voltage values.
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Homework Statement


What is the potential in the batteries "negative part"?
http://imgur.com/7nuxgC3

Homework Equations


3. The Attempt at a Solution [/B]
I don't know how to think...
My total resistance is:
[(1/50) + (1/75)]^-1 + 10 = 40 ohm
I=V/R = 36/40 = 0.9
The voltage on the 10ohm resistance is 0.9 *10 = 9V
Now I know that the voltage on the parallell resistances is 36-9 = 27v
Now I have to go from ground :

0 - 27 - 9 = -36

But this is wrong... I don't understand why
 
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Drizzy said:

Homework Statement


What is the potential in the batteries "negative part"?
http://imgur.com/7nuxgC3

Homework Equations


3. The Attempt at a Solution [/B]
I don't know how to think...
My total resistance is:
[(1/50) + (1/75)]^-1 + 10 = 40 ohm
I=V/R = 36/40 = 0.9
The voltage on the 10ohm resistance is 0.9 *10 = 9V
Now I know that the voltage on the parallell resistances is 36-9 = 27v
Now I have to go from ground :

0 - 27 - 9 = -36

But this is wrong... I don't understand why
The question is not worded very well, but I'm guessing they want you to say that there is +9V on the "positive" part of the battery and -27V on the "negative" part.
 
exactly but how do you know that it is 9 and -27?
 
Drizzy said:
exactly but how do you know that it is 9 and -27?
You correctly calculated the voltage across the 10 Ohm resistor as 9V. Since the right side of that resistor is grounded, the left side of the 10 Ohm resistor will be at +9V. Same deal with the right two resistors. Makes sense? :smile:
 
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yes! thank you :)
 
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