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In a circuit, a 10┬аvolt battery and three resistors R1тАЛ=2┬а╬й, R2тАЛ=3┬а╬й, and R3тАЛ=6┬а╬й are connected in parallel to each other. Which of the following is the correct value of effective resistance ReтАЛ and current I flowing through the circuit?
ReтАЛ=2┬а╬й,I=1┬аA
ReтАЛ=1┬а╬й,I=1┬аA
ReтАЛ=2┬а╬й,I=10┬аA
ReтАЛ=1┬а╬й,I=10┬аA
ReтАЛ=1┬а╬й,I=10┬аA
In a parallel circuit, the voltage across each resistor is identical to the source voltage, and the total effective resistance is calculated using the reciprocal sum formula. With a voltage of 10┬аV and parallel resistors of 2╬й, 3╬й, and 6╬й, the calculation leads to an effective resistance of 1╬й and a total current of 10┬аA based on Ohm's Law.
In a parallel circuit, the voltage across each resistor is identical to the source voltage, and the total effective resistance is calculated using the reciprocal sum formula. With a voltage of 10┬аV and parallel resistors of 2╬й, 3╬й, and 6╬й, the calculation leads to an effective resistance of 1╬й and a total current of 10┬аA based on Ohm's Law.
Think of parallel resistors like multiple checkout counters in a store; adding more paths reduces the total 'bottleneck' (resistance) for the shoppers (current) to flow through.
Parallel: 'Reciprocals add to make it small, the voltage stays the same for all.'
ReтАЛ1тАЛ=R1тАЛ1тАЛ+R2тАЛ1тАЛ+R3тАЛ1тАЛ тАФ Formula for equivalent resistance in parallel
I=ReтАЛVтАЛ тАФ Ohm's Law to calculate total current
For resistors in parallel, the reciprocal of the effective resistance ReтАЛ is the sum of the reciprocals of the individual resistances: ReтАЛ1тАЛ=R1тАЛ1тАЛ+R2тАЛ1тАЛ+R3тАЛ1тАЛ. Given R1тАЛ=2╬й, R2тАЛ=3╬й, and R3тАЛ=6╬й, we find ReтАЛ1тАЛ=21тАЛ+31тАЛ+61тАЛ=63+2+1тАЛ=66тАЛ=1╬йтИТ1, so ReтАЛ=1╬й. The total current I drawn from the battery is determined by I=ReтАЛVтАЛ=1╬й10┬аVтАЛ=10┬аA.
In parallel connections, potential difference across each resistor is constant and equal to the supply voltage.
The equivalent resistance in a parallel circuit is always less than the value of the smallest individual resistor.
Total current is the sum of currents flowing through each branch (I=I1тАЛ+I2тАЛ+I3тАЛ).
Each component operates independently.
Failure of one component does not stop the current flow in other branches.
Requires more wiring than a series circuit.
Cannot provide different voltage levels to components.
Household electrical wiring.
Power distribution in vehicles.
The calculation yields 1/ReтАЛ=0.5+0.333+0.166=1.0, hence ReтАЛ=1╬й.
Current is I=10┬аV/1╬й=10┬аA.
D is correct тАФ The calculation ReтАЛ1тАЛ=21тАЛ+31тАЛ+61тАЛ yields ReтАЛ=1╬й, and applying Ohm's law with V=10V gives I=10A.
Whenever you see resistors in parallel, always check if the equivalent resistance is smaller than the smallest resistor in the setтАФif not, you have miscalculated!