Module 4.3 Flashcards
What is Conservation of Energy?
Energy cannot be created or destroyed - it can only be transferred into different forms.
What is Internal Resistance?
The resistance to the flow of charge within a source. Internal resistance results in energy being dissipated within the source.
What is Kirchhoff’s second law?
A consequence of the conservation of energy. The sum of the voltages in any closed loop must equal zero.
What is Lost volts?
The difference between a source’s emf and the terminal voltage. It is equal to the potential difference across the source’s internal resistance.
What is parallel circuit?
Components are said to be connected in parallel when they are connected across each other.
What is Potential divider?
A method of splitting a potential difference, by connecting to resistors in series. The total potential difference is split in the ratio of their resistances.
What is Resistor in Parallel?
The potential difference across resistor connected in parallel is identical for each resistor. The current is split between the resistors. The total resistance is equal to the inverse of the sum of the resistances of the resistors.
What is Resistors in Series?
The current through resistors connected in series is identical for each resistor. The potential difference is split in the ratio of their resistances. The total resistance is equal to the sum of the resistance of the resistors.
What is Sensor circuits?
A circuit that reacts to external conditions. They commonly involve a semiconductor connected in a potential divider arrangement.
What is Series circuit?
Components are said to be connected in series when they are connected end to end.
What is Terminal PD?
The potential difference across the terminals of a power source. It is equal to the source’s emf minus any voltage drop over the source’s internal resistance.
Describe an experiment to determine the internal resistance of a source?
- Set up a circuit with a source, ammeter and variable resistor in series and a voltmeter in parallel.
- Vary the resistance and measure the voltage and current (take several readings).
- Plot a V-I graph.
- V = -rI + ε corresponds to y = mx + c
- The internal resistance = -m (-gradient)
