A variable resistor is very important in a circuit, because it allows you to build a circuit with some degree of control. For example, a volume knob can be a variable resistor. It can act as a control on the amount of current flowing.
This depends mostly on the circuit it is used in. Some typical purposes are:
Variable resistors (often called a rheostats or potentiometers) are commonly used in light dimmer knobs and volume knobs. By turning the knob to minimize the resistance, more current flows, and the light is brighter or the volume louder. By turning the knob to maximize the resistance, less current flows, making the light more dim or the volume lower.
A variable times the same variable is called a square of that variable. For example, if the variable is x, then x multiplied by x is written as x^2, which is read as "x squared."
In the first circuit with a 6V battery in series with 1 ohm and 2 ohm resistors, you can use Ohm's Law (P = V^2 / R) to calculate the power used in the 2 ohm resistor. First, find the total resistance of the circuit: 1 ohm + 2 ohm = 3 ohms. Then, calculate the current flowing through the circuit using V = IR. Finally, use P = V^2 / R with the resistance of the 2 ohm resistor to find the power. In the second circuit with a 4V battery in parallel with 12 ohm and 2 ohm resistors, first calculate the equivalent resistance of the parallel circuit using the formula (1/Req = 1/R1 + 1/R2). Once you have the equivalent resistance, use Ohm's Law (P = V^2 / R) to find the power used by the 2 ohm resistor.
The voltage across the resistor can be found using Ohm's law: Voltage = Current x Resistance. Thus, Voltage = 2 amps x 12 ohms = 24 volts.
In Table 2.1, the variable that is typically kept constant is referred to as the control variable. This variable is maintained at a consistent level across different experimental conditions to ensure that any changes in the dependent variable can be attributed to the manipulation of the independent variable.
A resistor may burn out due to excessive power dissipation, which can be predicted by calculating the power across the resistor using P = I^2 * R or P = V^2 / R, where P is power, I is current, V is voltage, and R is resistance. If the calculated power exceeds the resistor's power rating, it is likely to burn out. Additionally, factors like ambient temperature, resistor material, and external stresses should also be considered in predicting resistor burnout.
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If the DC voltage of 120 volts is feeding series circuit consisting of 2-ohm, 6-ohm, and 8-ohm regular resistors, the variable resistor for line ammeter to indicate 1.5 amp, the variable resistor must be fixed before the amp.
2 terminals. One is connected to the sliding contact. Other is to the coil of wire.
1.)Linear Resistor 2.)Non Linear Resistor a.)Fixed Value Resistor b.)Variable Resistor c.)Package Resistor Taking into account compositon: 1.) Carbon piece 2.) Carbon Deposition 3.) High Volatge Ink Film 4.) Metal Film 5.) Metal Glaze 6.) Wire Wound 7.) Ceramic Metal
i don't know about the uses but i know the advantages of carbon resistors.they are:1.they are compact. 2.they are inexpensive.
You need to drop 6 volts across the resistor. -- The resistor you need is 6/(the current in amps that your 6vdc device uses to operate) ohms. Example: If the device uses 1/2 Amp when it's running, then you need a 6/0.5 = 12-ohm resistor. -- And the power-dissipation rating of the resistor has to be at least 36/resistance watts. Example: For the 12-ohm resistor in the last example, it needs to be a (3-watt or more) resistor.
Reference variable is an alias name for a previously defined variable. Its use is that the same data object can be referred by 2 names and then can be used interchangeably.
1. Control the volume of a speaker, i.e. the volume knob on a transistor radio. 2. If attached to a pedal or door hinge, you could use the measured resistance to determine the angle. This would need some calibration in order to be accurate however.
Its the 2- ENGINEER what grade r u in?
lower the voltage by using a different power source or by placeing a variable resistor in series with the light bulb.
AnswerMy thoughts are that it is used to set the trigger point where the trigger fires. That is to say, if the voltage exceeds the reference set point, the trigger will then fire.To independently control the upper threshold and the lower threshold, some Schmitt trigger gates have 2 variable resistors: * a voltage-divider potentiometer, where the center tap selects the "average threshold"* a feedback variable resistor, which adjusts the amount of hysteresis (the difference between the upper threshold and the lower threshold).
If a variable has possible values -2 6 and 17 then this variable is an Integer.