1.A conductor is a material through which electrons can flow easily.
2.In addition to metals, certain gases are also used as conductors under special conditions.
3.Electrons move through a circuit conductor from the negative to positive terminal of the energy source.
4.Electronic collisions reduce the rate at which electrons flow through the conductor.
5.The basic unit of resistance is the ohm.
6.The Greek capital letter omega is used as an abbreviation for ohms after a numerical value. This letter is written as 
.
7.In almost all metal conductors, the resistance increases as the metal’s temperature increases.
8.With two wires of the same length, the wire with the larger cross-sectional area has less resistance.
9.All insulating materials will conduct current if a high enough voltage is applied to them.
10.Resistors are used to control voltage and current.
11.A fixed resistor has a single value of resistance.
12.The two most common kinds of variable resistors are called potentiometers and rheostats.
13.The resistance of a potentiometer of a rheostat changes between the sliding-arm terminal and the terminals of the element.
14.The sliding arm of a potentiometer of a rheostat is attached to the shaft of the device.
15.A potentiometer is most often used to vary the value of the voltage of the device.
16.The resistance element in a carbon composition resistor is mainly graphite or some other form of solid carbon.
17.The resistance element of a wire-wound resistor is usually nickel-chromium wire.
18.In a film resistor, a film of carbon or metal is deposited on the substrate.
19.The actual resistance of a resistor may be greater or less than its rated value, a variation known as the tolerance of the resistor.
20.A resistor that has an actual value that is very nearly equal to its rated value is called a precision resistor.
21.The power rating of a resistor indicates how much heat the resistor can handle before it burns in two.
22.The physical size of a resistor has nothing to do with its resistance.
23.A larger resistor of a given value has a greater power rating than a smaller resistor of the same value.
24.The first three stripes of the resistor color code indicate the resistance value of a resistor. The fourth stripe shows the tolerance of the resistor.
25.Resistors seldom become defective unless too large a current passes through them.
The overheating of a carbon-composition or film resistor often causes the resistance of the resistor to increase.
