2.3 D.C. Circuits Flashcards
What is current measured in?
A, Amperes
How is current in a circuit measured?
With an Ammeter in series
Ammeters have …
Negligible resistance
Electrical current
The rate of flow of charge
The value of current in series is …
The same at all points
The value of current in parallel branches of a circuit …
Adds up to equal to the total current value
When a current enters a junction the …
Sum of the current entering is equal to the sum of the current exiting. due to the conservation of charge
What is potential difference measured in?
V, volts
How is potential difference measured?
With a Voltmeter in parallel across the component
The Potential difference across two components … the potential difference across the …
Equals
Source
The sum of the potential difference across components in a series circuit is …
Equal to the potential difference across the supply. This is a consequence of the conservation of energy
The potential difference across parallel components is …
All the same
The total resistance in a series circuit is the …
sum of all the resistances of the individual components
The total resistance in a parallel circuit is the …
sum of all of the resistances under one. Since the current is split more times the resistance will be less
Resistivity
The resistance of a wire of the material of unit length
Resistance
Is the volts per ampere
What is a potential divider used for?
The potential divider is used to control the amount of volts supplied to a certain component. by using other resistors to take portions of the unwanted V
EMF, Electro Motive Force
Of a source is the energy converted from some other form into electrical potential energy per coulomb of charge passing through the source
What is the unit of EMF?
V, Volt, same as potential difference
What is the equation for internal resistance
V = E - Ir
E = emf
V = P.d
Ir = lost volts or Internal resistance
