Calculating voltage across resistors

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To calculate the voltage at point X in a circuit with a 500V source, a 1MΩ resistor (R1), and a 10kΩ resistor (R2), use the voltage divider formula: V = 500 * R2 / (R1 + R2). For the first scenario, substituting the values gives X = 4.76V. In a more complex circuit with additional resistors (R3 and R4), the same principles apply, requiring the calculation of total resistance and current before determining voltages at points X, Y, and Z. Ohm's law (V = IR) is essential for these calculations, ensuring accurate voltage readings across each resistor. Understanding these formulas allows for effective voltage analysis in resistor networks.
ingram010
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Hi all,

I am looking for a formula to work out the following-


500v---/\/\/\/\/---X---/\/\/\/\/---0v
1megohm 10kohm

what is X?

cheers
 
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Welcome to PF. Its not clear at least to me what the problem is, is X an unknown voltage. If so
use V=iR first compute i using the total series resistance (here the sum of 1Mohm and 10Kohm.
Then V is just the i*the resistance over which you want to find voltage.

or all in one v=500*R/(R+r) This is just voltage divider eqn. Thats the voltage across the first resistance, voltage across the second would be:

500*r/(R+r), if your looking for the value of x, this would be the one to use.
 
Last edited:
voltage calculation

Hi, on reflection it isn't very clear. Sorry.


how about this-

500v---\/\R1\/\----X----\/\R2\/\---0v

If R1 = 1Mohm and R2 = 10Kohm
what is the voltage at X?

Or this one -

500v---\/\R1\/\--X--\/\R2\/\--Y--\/\R3\/\--Z--\/\R4\/\---0v

If R1 = 1Mohm, R2 = 10Kohm, R3 = 10Kohm and R4 = 10Kohm
what is the voltage at X,Y and Z?

is there a simple calculation for this problem?
 
first find the electric current
then use Ohm's law
V=IR
500=I(106+103)
I = ?
1
V = IR
X - 0 = I(R2)

2
V = IR
500 - X = I(R1)
 

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