Pmt Flashcards
What is electric current (I)?
The flow of charge per unit time, or the rate of flow of charge.
I = Q/t, where Q is charge and t is time
What is the formula for potential difference (V)?
V = W/Q, where W is energy transferred and Q is charge.
Potential difference is the energy transferred per unit charge between two points in a circuit.
How is resistance (R) defined?
Resistance is a measure of how difficult it is for charge carriers to pass through a component, calculated by R = V/I.
R is measured by dividing the potential difference across a component by the current flowing through it.
What does Ohm’s law state?
For an ohmic conductor, current is directly proportional to the potential difference across it, provided physical conditions are kept constant.
This means that if you increase the voltage, the current increases proportionally.
Describe the current-voltage graph of an ohmic conductor.
It will look like a straight line through the origin.
This linear relationship is valid as long as physical conditions remain constant.
What is a semiconductor diode?
A component that allows current to flow easily in one direction (forward bias) but has high resistance in the opposite direction (reverse bias).
The forward bias allows current to flow past the threshold voltage, while reverse bias results in extremely high resistance.
Fill in the blank: The forward bias of a diode is the direction in which it will allow current to flow easily past the _______.
threshold voltage.
The threshold voltage is the smallest voltage needed to allow current to flow through the diode.
True or False: The resistance of a diode is low in reverse bias.
False.
In reverse bias, the resistance of the diode is extremely high, allowing only a very small current to flow.
