Series Circuits
A series circuit is the most basic type of circuit there is. A series circuits connects loads one after another in a single path.
Parallel Circuits
The next type of circuit is where one load is connected side by side, where there is more than a single path for the current to travel through.
The rate of charge flow measured in Ampres (Coulombs/seconds). It is summarized using the Formula I (A) = Q(C)/t (s). To measure current, an ammeter is used and it measures the amount of coulomb that passes through a given distance over a period of time. An ammeter must be connected through a simple circuit. (1 electron = 1.602 x 10^-19 C)(1Coulomb = 6.2x10^18 Electrons)
The amount of current flow in a circuit (the amount of energy transferred to a device) depends on two factors:
1) The potential difference of the power supply (the amount of push)
2) the nature of the pathway through the loads that are using the electric potential energy
Direct Current
In a direct current or DC, the current flows in one direction from the power supply through the conductor to a load.
Alternating Current
In an AC, the electrons periodically reverse the direction of their flow. This reversal is carried out with he help of electric and magnetic forces.
Conventional current vs Electron flow
Electron flow is now the "well understood" theory where the current flow is a negatively charged electron repelling one another. From a negative terminal (-) to a positive terminal (+).
However in Conventional current the current flow was thought to move from the positive terminal to the negative terminal of any power supply.
Electrical Potential Difference (Voltage)
Electrical Potential Difference (Voltage) describes the amount of energy each coulomb of charge in a circuit releases to the load. Voltage is measured in Volts (V or J/C) and uses a voltmeter to measure the potential difference between two points, HOWEVER a voltmeter must be connected in parallel with a load. The formula for Voltage is V(V) = W (J) / Q(C) Sometimes W(work) is replaced with E (energy) in base formulas.
Voltage and Current
Because V=E/Q and I=Q/t
therefore E= VQ and Q= It
Hence E=VIt
Resistance (Ohm's Law)
Electrical Resistance is just as its name suggest, it is the amount of opposition to a flow of a current.
In Ohm's Law, it suggest that R = V/I because the Voltage to Current ration was constant for a particular resistor.
The resistance of a conductor often depends on its length (if length is doubled, resistance is doubled), cross-sectional area(if the area is doubled, the resistance goes to half of its original value), the material it is made of and its temperature.
Conservation of Electric charge
Kirchhoff's Current Law: the total amount of current into a junction point of a circuit equals the total current that flows out of that same junction
Kirchhoff's Voltage Law: the total of all electrical potential decrease in any complete circuit loop is equal to any potential increases in that circuit loop
Series
It=I1=I2=I3..=In
Vt=V1+V2+V3+...Vn
Rt=R1+R2+R3+...Rn
Parallel
It = I1+I2+I3+I4+...In
Vt=V1=V2=V3=Vn
1/Rt= 1/R1+1/R2+1/R3+.....1/Rn
Power
Power is the rate at which work is done.
For each particular load, a coulomb of charge is the energy carrier and the electric potential is the amount of energy that the charge is carrying. Therefore the amount of power dissipated in the load depends on how fast the charge arrives at the load.
Power has several formulae (power uses the units Watts or J/s)
P(W)=E(J)/t(S)
Since E=VIt
P=VIt/T
P= VI
Or
Because R=V/I
V= IR
P=I^2R
Therefore
P=IV
P=V^2/R
P= I^2R
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