What is variable resistor do?
Variable resistor A resistor limits the passage of electrical current. A fixed resistor has a resistance that does not change. The resistance of this resistor is changed by moving the position of a slider. A variable resistor is used in some dimmer switches and volume controls.
Can a Transistors be used as a variable resistor?
A transistor within an electronic circuit works like a combination of a diode and a variable resistor, also called a potentiometer or pot. This changes the resistance of the potentiometer, which in turn changes the amount of current that can flow through the collector-emitter path.
What is a variable resistor in simple words?
A variable resistor is a resistor of which the electric resistance value can be adjusted. A variable resistor is in essence an electro-mechanical transducer and normally works by sliding a contact (wiper) over a resistive element. These resistors are called digital potentiometers.
What does a resistor do ks3?
A resistor is an electrical component that restricts the flow of electric current. When resistors are connected in parallel, the combined resistance of two or more resistors is less than that of either resistor by itself.
Why do we use variable resistors?
Variable resistors are widely used in electric circuits to adjust the value of current or voltage, since the resistance of variable resistors can be set to a certain value. Variable resistors allow you to adjust the value of voltage by changing the resistance and keeping current constant .
What are types of variable resistor?
The different types of variable resistors include:
- Potentiometer.
- Rheostat.
- Thermistor.
- Magneto resistor.
- Photoresistor.
- Humistor.
- Force sensitive resistor.
Is potentiometer a variable resistor?
A potentiometer is a three-terminal resistor with a sliding or rotating contact that forms an adjustable voltage divider. If only two terminals are used, one end and the wiper, it acts as a variable resistor or rheostat.
Why do variable resistors have 3 pins?
To use the potentiometer as a voltage divider, all the three pins are connected. One of the outer pins is connected to the GND, the other to Vcc and the middle pin is the voltage output. Basically, the voltage divider is used to turn a large voltage into a smaller one.
What does a resistor do ks2?
What’s a Resistor? The resistor is the part of an electrical circuit that resists, or limits, the power of an electrical current in a circuit. The resistor also helps to reduce, or lessen, the amount of electricity moving through the circuit.
When do you use a variable resistor connection?
Variable Resistor Connection. It is used as a rheostat when one end of the resistance track and wiper terminal are connected to the circuit and other terminal of resistance track remains open. In this case the electrical resistance between connected terminal and wiper terminal depends upon the position of the wiper (slider) on the resistance track.
When is a variable resistor used in a trimmer?
Whenever variable resistors are used to tune or calibrate a circuit or its application or trimmer potentiometers or trimpots are used, these are generally less rated potentiometers which are mounted on the circuit board, and are adjustable by using a screwdriver.
Is there a Micro version of a variable resistor?
Preset Variable Resistor. This is micro version of variable resistor. Preset resistors are directly mounted on circuit board and adjusted only when the circuit is built. There is an adjustable screw attached to the resistor and a small screwdriver is required to adjust this screw for desired resistance value.
What kind of track is used in a variable resistor?
It mainly consists of a resistance track and a wiper contact. The wiper contact moves along the resistance track when the adjustable component is adjusted. There are mainly three different types of resistance track used in this resistor they are carbon track, cermet (ceramic and metal mixture) track and wire wound track.