# physics circuit question calculating current and p.d for resistors

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#1
photo attatched - i worked out the 18Ω one to be 12V and 0.6 amps is this right? and also how do i work out the other 2 and how the voltage splits
Last edited by gogman12345; 1 month ago
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1 month ago
#2
The 18 ohm resistor will not have a pd of 12v. But the current will be .6 at this resistor.
You have correctly calculated the current at the 18 ohm resistor of 0.6 amps, i assume by using 1/r+1/r=1/R to calculate the total resistance of the resitors in parralel then added the 18 ohms the ohms law to get current.

Using .6 as the current use ohms law to get the pd of this resistor.
The rest of the pd is distributed into the reisotors in parrallel. They both have the same potential difference and their currents will add to .6. Rember for circuits in parralell the pd is the same on each stem and the sum of the current in each stem adds to the current at the terminal.
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#3
(Original post by Dominininc)
The 18 ohm resistor will not have a pd of 12v. But the current will be .6 at this resistor.
You have correctly calculated the current at the 18 ohm resistor of 0.6 amps, i assume by using 1/r+1/r=1/R to calculate the total resistance of the resitors in parralel then added the 18 ohms the ohms law to get current.

Using .6 as the current use ohms law to get the pd of this resistor.
The rest of the pd is distributed into the reisotors in parrallel. They both have the same potential difference and their currents will add to .6. Rember for circuits in parralell the pd is the same on each stem and the sum of the current in each stem adds to the current at the terminal.
thanks alot
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#4
what did you work out the 3Ω and 6Ω current and p.ds so i can check my answer
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1 month ago
#5
(Original post by gogman12345)
what did you work out the 3Ω and 6Ω current and p.ds so i can check my answer
Because the pd is the same in each (12-10.8=1.2V) Ohms law so for the 3 ohm it will be .4 and the 6 will be .2 amps
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#6
(Original post by Dominininc)
Because the pd is the same in each (12-10.8=1.2V) Ohms law so for the 3 ohm it will be .4 and the 6 will be .2 amps
ok thanks alot have a nice day
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