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A variable resistor is used in cicuits to vary the magnitude of resistance passing through the resistor. It is commonly used to change the value of current across a circuit to find relationships of current and voltage.
Wiki User
∙ 15y ago
Wiki User
∙ 12y agoA variable resistor is used in cicuits to vary the current passing through the resistor. It is commonly used to change the value of current across a circuit, or to act as a voltage divider.
They are commonly equiped with a knob outside of a cabinet, to enable the user to adjust the operation of a circuit, like a volume control on a radio or amplifier.
Wiki User
∙ 12y agoAs the name suggests, it is a resistor, but you can change it's value using a linear slider or a rotary knob.
The function is, to enable the user of a piece of equipment, to alter the value of a resistor and change the operation of the workings, without dismantling it.
The most common example would be the volume control of an audio amplifier.
They are usually made by laying down a film of carbon, onto a horse shoe shape, or straight stip of plastic. each end is terminated and forms a single resistor.
In addition there is a wiper which runs along the carbon, controlled by a knob.
The contact will pick of a varying resistance compared to each end, depending on it's position. It will have zero resistance at one end and the maximum value of the resistor at the other end.
This also known as a 'potentiometer' as when used with three contacts, varying potential can be selected with the slider.
They are made with different maximum resistances for different applications.
They can also have different compositions of carbon, to make the change in the resistance be linear or logarithmic, along the length of the track.
There are other types of variable resistor for specialist use.
Some use wire instead of carbon.
Some vary the resistance by applying pressure to a capsule containg carbon.
Wiki User
∙ 14y agoMain matterial of variable resistor is same with constant value resistor. Assume that there is a cylindrical resistive material in the component and the resistance of the material depends on its lenght. When you adjust the variable resistor, it changes the lenght of active part of the resistive material so the output resistance changes.
Wiki User
∙ 15y agoWhen one wants to regulate something variable resistors are used.
Like: volume in headset, light intensity, temperature in heating devices etc.
Wiki User
∙ 10y agoA rheostat.
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Why you use resistor with variable resistor?
Often we want to easily change a resistor value, so we use a variable resistor. For example, we may want to change the resistor that controls the power sent to a LED, so we can easily make it brighter or dimmer. Often if we use a variable resistor, there is only a very narrow range that is useful. Continuing our example, sometimes we use several LEDs, and we use the variable resistor to set them all to the same brightness. In this case, the resistance range that sets the LED to be twice as bright as the the other LEDs, and the resistance range that sends so much power to the LED that it is permanently destroyed is even less useful. So we add a fixed resistor in series with the variable resistor -- the fixed resistor sets the minimum net resistance, no matter how we turn the knob on the variable resistor. In our example, the addition of the fixed resistor allows us to turn the variable resistor throughout its whole range, and the LED gets brighter and dimmer; without that resistor, a certain range of the knob on the variable resistor would allow so much power to go to the LED that it would be destroyed.
What is the center terminal of a variable resistor called?
The center terminal of a variable resister is called a wiper.
List three variable resistor and list three fixed resistors?
mmg
What happens to the reading on an ammeter if the value of a variable resistor is increased?
it explodes and burns everyone in the room.
What is the advantage of including a variable resistor rather than a fixed resistor of know size in a potential divider that includes and LDR or a thermistor?
a three prong calisator with intermittent interphase
How do you test a variable resistor?
how do test a variable resistor
How connect a variable resistor to circuit?
how connect a variable resistor to circuit
Where is a variable resistor in your home?
If you have a light switch where you can brightener it or dim it that is a VARIABLE RESISTOR.
Does a variable resistor have a bias?
A variable resistor means that the resistance can be varied, usually by using a slide. A fixed resistor can not be varied.
Is Light dependent resistor an example of resistor?
yes, a variable resistor
Function of a variable resistor?
Variable resistor is an resistor that can change its resistance manually, by rotating a handle or a screw.
What is the difference between a fixed resistor and a variable resistor?
its the colour of the fixed and the variable we define it by its power and name
What is a variable resister?
The volume knob on an audio device (radio, TV) is an example of a variable resistor. A variable resistor is also known as a potentiometer.
What is variable resistance?
The volume knob on an audio device (radio, TV) is an example of a variable resistor. A variable resistor is also known as a potentiometer.
What is a resistor whose value can varied over a range of value called?
Variable resistor. The value of the variable resistor can be changed at any given moment.
Are transistor the same as the variable resistor?
no
Difference between variable and fixed resistor?
Variable resistors means that a resistor which can change its resistance by control by any person or it self and fixed resistor means that it can not change its value.
