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Electrical resistance circuits arranged in series

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					Electrical resistance circuits arranged in series
The series is one of the series circuit are arranged in parallel (series).

The series of lights as the picture below is called a series circuit. Because the parts of a
series circuit are connected one after the other, the same amount of current flowing to all
parts of the circuit. If you are connecting three ammeters into the circuit as shown in the
figure, the three ammeters that will show the same price.



What happens if one of the parts of a series circuit is disconnected? Electric current in a
series circuit has only one path that can be bypassed. So if there's a broken part, means
the circuit is open and the current would not flow.
In the picture above, in series, the voltage source, Vsumber, is equal to the amount of
stress on the lights A and B,


V. source = VA + VB

Since the current I through the lights of the same size, then

VA = VB = IRA and IRB

Therefore, the

V. source = IRA + IRB or

V. source = I (RA + RB)

The current flowing through the circuit can be calculated by the following formula.

This equation applies to any number of serial obstacles, not just two like the picture
above. Same current will still flow when a single resistor, R, has a resistance equal to the
number two barrier lamp. Such barriers are called equivalent series resistance or circuit.
For the series resistance, equivalent resistance equal to the total number of series
connected resistance.

R = RA + RB

for two series connected barriers, and

R = RA + RB + RC

for three series connected resistance, and so on.
Note that the equivalent resistance is always greater than any single obstacle connected
series. Therefore, if the battery voltage is not
changed, adding more devices in series is always lower current. To calculate the current,
I, flowing in a series circuit, first
calculate the equivalent resistance, R, and then use the following equation to calculate I.
I = V. source / R
I = Strong electric current (A)
V = Voltage (V)
R = electrical resistance (Ohm)

sample questions:
resistor 20 Ω, 30 Ω resistor and a 10 Ω resistor is connected in series on the ends of the
battery is 90 V. what is the equivalent resistance circuit? What is the current in the
circuit? Calculate the voltage at the ends of each of these!

Given:

RA = 20 Ω
RB = 30 Ω
RC = 10 Ω (strung together series)
V. source = 90 V

Asked:
1. Barriers substitute R
2. Strong currents I
3. Different voltages on each obstacle, VA, VB, VC

Answer:
1. R = RA + RB + RC
R = 20 Ω +30 Ω +10 Ω
R = 60 Ω

2. I = Vsumber / R
I = 90 V / 60 Ω
I = 1, 5 A

3. VA = IxRA
VA = 1.5 A x 20 Ω = 30 V

VB = IxRB
VB = 1.5 A x 30 Ω = 45 V

VC = IxRC
VC = 1.5 A x 10 Ω = 15 V

				
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posted:10/1/2012
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Description: all about physics educations