Series And Paralel Circuits Essay, Research Paper

Ohm’s law states that current in a resistance varies in direct proportion to voltage applied and inversely proportional to resistance.It is the relationship between voltage, current, and resistance. (V=IR) When more then one resistor is connected to a circuit they can be in either series or parallel patterns.

A series circuit is one that the components are connected end to end so that current has only one path to follow through the circuit. In a series the current entering each resistor is the same therefore with similar resistance.

I1 = I2 = I3

Veq = V1 + V2 + V3

Req = R1 + R2 + R3

A parallel circuit is one that is an electrical circuit with two or more resistance units so wired as to permit current to flow through both units at the same time. Unlike the series circuit, the current in the parallel circuit does not have to pass through one unit to reach the other. For parallel the current through each resistor is equal to the sum of the current.

Ieq = I1 + I2 + I3

Veq = V1 + V2 + V3

1/Req = 1/R1 + 1/R2 + 1/R3

A combination circuit is one that consists of a combination of series and parallel circuits on one circuit. In paralle. I is larger because current through each resistor has to be added to determine Ieq. In series the total current is equal to the current going through each individual resistor. For the parallel, series combination, the current for the parallel resistors is equal to the current going through the series resistors.

Resistors

R1 53 x 10 + 5% 53.3

R2 15 x 10 + 5% 149.2

R3 39 x 10 + 5% 387

Simulated

0% series A = 6.791 mA

parallel A = 112.7 mA

combo A = 24.91 mA

measured rheostat at 93.4 ohms

experimental

0% series = 6.74 mA

parallel = 38.85 mA mistake done by Dr. Anderson, not connected properly to

rheostat and ammeter.

Combo = 25.97 mA

Resistance measured off of Ammeter

10A = .2 ohms

40mA = 11 ohms

Series

Resistor before R1 6.52mA

Between R1 and R2 6.54 mA

Between R2 and R3 6.48mA

After R3 6.45mA

6.52 R1 6.54 R2 6.48 R3 6.45

Decrease in resistance due to the resistors internal resistance.

Parallel

R1 before 38.99mA

Before R1 26.95 mA = after

Before R2 10.32mA = after

Before R1 4.13mA = after

Before and after are equal. Goes back into rheostat at 38.88mA

26.95 R1 26.95

38..9 10.32 R2 10.32 38.88

4.13 R3 4.13

Although the current entering and leaving the resistors is the same, there should be a slight drop due to the internal resistance of the resistors. This can be seen from the differing values of the current entering and leaving the parallel group of resistors.

Combination

Potential difference 3.692v

Current of entire circuit 0.023mA

Current = 0.239mA

R2 , R3 = 163.4 ohms

R1, R2, R3 =218.4 ohms

The combination consists of a parallel and a series connection all on the same circuit.

Our results proved Ohm’s law. The results came out to prove that voltage is equal to current multiplied by resistance. If by any chance our results wouldn’t have come out, then this would most probably be due to the fact that we used old wires such as the gator gator or the banana gator wires in the circuit. This could also be due to a faulty rheostat. The connection of the circuit could be done wrong. Another factor that could affect the reading could be having a bad switch in the circuit. This could throw off the whole reading. In order to improve our results we could make sure to use a properly working rheostat, brand new wires, have our circuits doule checked by the instructor to make sure they are connected correctly, and also make sure that the switch is in proper working order. If we were to do the whole experiment again just to see if the results would be different because of a faulty switch, we could set up the circuit exactly as stated in the lab manual only this time without a switch in place. This would allow full connection throughout the circuit without having to worry about a faulty switch.