- #1
Calculate Current Through R3: Negative Possible?
In summary, the current through R3 can be calculated by using the equation -10V+I3R3+I2R2=0 for loop 2 and the equation 5-I3R3-I1R1=0 for loop 1. A negative current is a legitimate answer, as long as a direction arrow is shown, and it indicates that the current is traveling in the opposite direction of the arrow. The equations provided in the attempt at a solution were incorrect and needed to be revised.
- #2
lewando
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It is a legitimate answer provided you show a direction arrow (which you have done). It means that the current is not traveling in the direction indicated by your direction arrow. It is going in the opposite direction.
- #3
lewando
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Looking at your loop equations, they seem a bit suspect. If you are summing the changes in voltage across each element along a loop, equating the sum to zero, you should get something different.
- #4
ehild
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Sastronaut said:
Your equations 1 and 2 are wrong. Note, that the potential decreases in the direction of the current.
ehild
- #5
Sastronaut
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What should my equation for loop 1 be?
- #6
ehild
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You start at the negative pole of the battery, and follow the change of potential in the direction, indicated by the green arrow. The potential increases by 5 V traversing the battery. Then it decreases by I3R3 along R3. Then again, it decreases by R1I1, when you return to your initial position. The net change of potential is zero: 5-I3R3-I1R1=0.
Do the same for the other loop. Note that going in direction opposite to the current, the potential would increase.
ehild
Do the same for the other loop. Note that going in direction opposite to the current, the potential would increase.
ehild
- #7
Sastronaut
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okay I think I am following you so for loop 2 the equation is then -10V+I3R3+I2R2=0?
- #8
ehild
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Sastronaut said:
Yes.
ehild
FAQ: Calculate Current Through R3: Negative Possible?
What is the formula for calculating current through R3?
The formula for calculating current through R3 is I = V/R, where I is the current in amps, V is the voltage in volts, and R is the resistance in ohms.
Can the current through R3 be negative?
Yes, the current through R3 can be negative if the voltage and resistance values are such that the resulting calculation is negative. This indicates that the current is flowing in the opposite direction.
How do I determine the voltage and resistance values for R3?
The voltage and resistance values for R3 can be determined using a multimeter or by analyzing the circuit diagram. The voltage can also be provided in the circuit or calculated using Kirchhoff's voltage law.
What factors can affect the current through R3?
The current through R3 can be affected by changes in the voltage or resistance values, as well as changes in the overall circuit configuration or components. Temperature can also affect the resistance, which in turn can impact the current through R3.
How does the current through R3 affect the rest of the circuit?
The current through R3 is a crucial component in determining the overall current flow and voltage drops in the circuit. It can affect the operation of other components and impact the performance of the circuit as a whole.