3.7 Resistors Flashcards
The electrical energy applied to a resistor is converted completely into?
Heat
What is the purpose of a potentiometer?
Vary the resistance (e.g. the volume control)
What is the purpose of a rheostat?
Used for calibration purposes, it can be set to a specific value, using for instance a screwdriver, and then are not touched again.
One example is compass compensation.
How does a voltage dependent resistor work?
The resistance value changes according to the applied voltage
How does an increase in voltage affect a voltage dependent resistor?
The resistance of a VDR resistor decreases as the voltage increases
What are the two type of temperature dependent resistors?
NTC Resistors (negative temperature coefficient)
PTC Resistors (positive temperature coefficient)
How is a NTC Resistor affected by an increase in temperature?
Resistance decreases as the temperature increases
How does an increase in temperature affect a PTC resistor?
Resistance increases as the temperature increases