Calculating V1 and R3 in a Parallel Circuit with Given Resistors and Currents

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To calculate V1 and R3 in a parallel circuit with R1 at 8 ohms and I1 at 0.75A, the voltage V1 is determined using Ohm's Law, yielding 6V. R2, with a value of 5 ohms, has a potential difference of 30V, leading to 24V across R3. The current through R3 is 6A, allowing for its calculation as 4 ohms. The total resistance in the parallel circuit is derived from the formula 1/Rt = 1/R2 + 1/R3. Ultimately, the calculated values for V1 and R3 are 6V and 1 ohm, respectively.
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Determine V1 and R3 if R1= 8ohms I1= 0.75A, R2=5 Ohms and I2=6A. Note that R2 and R3 are connected in parallel. Thank you.
 
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V1 you can calculate by using V=IR on the first resistor which turns out to be 54V (remember I is the sum of both I1 and I2 as current is split between two components in series and we can treat the parallel system to be a series entity). Secondly taking into account the fact that V is then split in parallel but current is not we can work out R2 has a potential difference across it of 30V leaving 24V across R3 which has I3=6A. Thus R3=4 Ohms.
 


To determine V1 and R3, we can use the formula for calculating the total resistance in a parallel circuit: 1/Rt = 1/R2 + 1/R3.

First, we need to find the total resistance of R2 and R3. Plugging in the given values, we get:

1/Rt = 1/5 + 1/R3

Next, we can solve for Rt by finding the reciprocal of both sides:

Rt = 1/(1/5 + 1/R3)

Now, we can use Ohm's Law (V=IR) to find V1. Plugging in the given values for R1 and I1, we get:

V1 = R1 * I1 = 8 * 0.75 = 6V

Lastly, we can use Ohm's Law again to find R3. Plugging in the values for V1 and I2, we get:

R3 = V1 / I2 = 6 / 6 = 1 Ohm

Therefore, the values for V1 and R3 are 6V and 1 Ohm, respectively. I hope this helps!
 
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