Electric circuits Flashcards
Electric current
Rate of flow of charge. Measured in Amperes (A)
EMF
The electromotive force of the battery. It indicates the energy supplied by the battery per coulomb (C) of charge.
Potential difference
Energy used per coulomb (C) charge by the components between 2 points in a circuit.
State Ohm’s law
Potential difference (V) across a resistor is directly proportional to the current (A) through the resistor, provided that the temperature remains constant.
V = IR
Ohmic conductor
A conductor with a resistance that is constant for a wide range of values of voltage and current.
Non-ohmic conductor
A conductor with a resistance that is different for different values of voltage and current
Total resistance in a series connection
Total R= R1+R2+R3…
Total resistance in a parallel connection
1/Total R= 1/R1 + 1/R2 + 1/R3…
Don’t forget to flip fractions after adding together
Total current in a series connection
i total = i1 = i2 = i3…
lower case “i” to prevent confusion , but should a an upper case “I”
Total current in a parallel connection
i total = i1+i2+i3…
lower case “i” to prevent confusion , but should a an upper case “I”
Total voltage in a series connection
V total = V1+V2+V3…
Total voltage in a parallel connection
V total = V1 = V2 = V3
Resistance
Obstacle to flow of charge, measured in ohms (Ω)
Power
Rate at which work is done, measured in watts (W)
Multiple formulas:
P= W/▲t = VI = V^2/R = I^2/R
Electrical energy transfered
Depends on the power of the appliance as well as amount of time it is switched on
E= P x ▲t