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What is resistor?
The resistor is the most common and well-known of the passive electrical components. A resistor resists or limits the flow of electric current in a circuit. There are many uses for resistors: they are used to drop voltage, limit current, attenuate signals, act as heaters, act as fuses, furnish electrical loads and divide voltages.

What is the function of resistor?
In electronic circuits, resistors are used to reduce current flow, adjust signal levels, to divide voltages, bias active elements, and terminate transmission lines, among other uses.

What is difference between resistor and resistance?
Resistance is the property of a conductor, which determines the quantity of current that passes through it when a potential difference is applied across it. A resistor is a electrical componet with a predetermined electrical resistance, like 1 ohm, 10 ohms 100 ohms 10000 ohms etc

What is Ohm’s law?
Ohm’s law is a simple equation that shows the relationship between resistance, voltage and current through a metal
wire, or some other type of resistive material. In mathematical terms, Ohm’s law is written as:
I = V/R, where I is the current (amps), V is the voltage, and R is the resistance.
Ohm’s law can also show the relationship between resistance, voltage and power using the following equation:
P = V2/R, where P is the power (watts), V is the voltage, and R is the resistance

What is the Power Rating of a resistor?
The power rating of a resistor is measured in watts, and it's usually somewhere between ⅛W (0.125W) and 1W. Resistors with power ratings of more than 1W are usually referred to as power resistors, and are used specifically for their power dissipating abilities.

What is the tolerance of a resistor?
The tolerance of a resistor is the maximum difference between its actual value and the required value and is generally expressed as a plus or minus percentage value. For example, a 1kΩ ±20% tolerance resistor may have a maximum and minimum resistive value of: Maximum Resistance Value.

What is the temperature coefficient (TCR) of a resistor?
TCR is expressed as the change in resistance in ppm (0.0001 %) with each degree Celsius of change in temperature. TCR is typically referenced at + 25 ˚C and changes as the temperature increases (or decreases). A resistor with a TCR of 100 ppm/°C will change 0.1 % over a 10 °C change and 1 % over a 100 °C change. In the context of a resistor network, the TCR value is called the absolute TCR in that it defines the TCR of a specific resistor element. The term TCR tracking refers to the difference in TCR between each specific resistor in a network.

What is the Short Time Overload (STOL) of a resistor?
Resistor manufacturers define an STOL (short-time-overload) condition, the degree of which varies depending on the type of resistor. For power wirewound resistors, STOL can be two to 10 times the rated power for 5 or 10 sec.

What is the Dielectric Withstanding Voltage (DWV) Testing?
A dielectric withstand test (or pressure test, high potential or hipot test) is an electrical test performed on a component or product to determine the effectiveness of its insulation. The test may be between mutually insulated sections of a part or energized parts and electrical ground. The test is a means to qualify a device's ability to operate safely during rated electrical conditions.

What is the Insulation Resistance (IR) Testing?
An insulation resistance (IR) test measures the total resistance between any two points separated by electrical insulation. The test, therefore, determines how effective the dielectric (insulation) is in resisting the flow of electrical current.

What is Maximum Overload Voltage of a resistor?
The maximum value of voltage capable of being applied to resistors for a short period of time in the overload test.
Typically, the applied voltage in the short time overload test is 2.5 times larger than the rated voltage. However, it should not exceed the maximum overload voltage.

What is Maximum Working Voltage of a resistor?
The maximum value of DC voltage or AC voltage (rms) capable of being applied continuously to resistors or element. However, the maximum value of the applicable voltage is the rated voltage at the critical resistance value or lower.

A type of resistor made from winding a metal wire, such as nichrome, on an insulating form, such as a ceramic, plastic, or fiberglass core.

What is Metal Film Resistor (Leaded/MELF)?
A type of cylindrical resistors made by depositing a resistive element made of a thin conducting film of a metal or metal alloy, such as nichrome, onto a cylindrical ceramic or glass core. The resistance is controlled by cutting a helical groove through the conducting film.

What is Metal Oxide Resistor (Leaded)?
A type of cylindrical resistor that uses materials such as ruthenium oxide or tin oxide as the resistive element. These resistors can be excellent high-voltage or high-power devices.

What is Thick Film Resistor (SMD/Chip Array/Networks)?
Specially built surface-mount film resistor that carries high power for the part size. For thick film resistors, the ruthenium oxide “film” is applied using traditional screen-printing technology.

What is Thin Film Resistor (SMD/Chip Array/Networks)?
A type of surface-mount film resistor with a relatively thin resistive element, measured in angstroms (millionths of an inch). Thin film resistors are made by sputtering (also known as vacuum deposition) a resistive material, such as nichrome or tantalum nitride, onto the surface of a substrate.

What is Carbon Film Resistor (Leaded/MELF)?
A general class description for cylindrical resistors made by depositing a carbon film on the surface of a center core insulator.

What is Carbon Composition Resistor (Leaded)?
A general class description for resistors consisting of a carbon mixture resistive core and a molded outer insulating core.

What is Metal Strip Resistor (SMD)?
A type of resistor constructed using a solid metal alloy, such as nichrome or manganesecopper, as the resistive element, which is then welded to copper terminals. Used in current sense and shunt applications.

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