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1.  Resistance can be described as the:

2.  The resistance of a material is most commonly determined by four factorslength, crosssectional area, type of material and:

3.  The resistance of a conductor is proportional to its:

4.  The resistance of a conductor is inversely proportional to its:

6.  Resistivity of a material is defined as the:

7.  The following formula can be used to determine the resistance of a length of conductor. In the formula the symbol ρ stands for the:

8.  A copper cable has a length of 450 m and a crosssectional area of 4.0 mm^{2}. If the resistivity of the copper is 1.72E8 Ωm, then the resistance of this cable will be:

9.  A 10 Ω resistor is to be made from manganin wire with crosssectional area of 0.2 mm^{2}. If manganin has a resistivity of 48 E–8 Ωm, then the required length of this size manganin wire will be:

10.  The temperature coefficient of resistance of a material is defined as the change in:

11.  For some materials, an increase in temperature causes an increase in resistance; these materials are said to have a:

12.  Look at the following graph: The above graph shows the effect of an increase in temperature on a copper conductor. The graph shows that the increase of resistance plotted against temperature is:

13.  The inferred zero formula for determining the resistance of a copper conductor is shown: In the formula, the term t_{2}stands for the:

14.  The resistance of a coil of copper wire is 30 Ω at 15ºC. Its resistance at 75ºC will be:

15.  An electric motor has a winding resistance of 15 Ω at 20ºC. After running up to temperature at full load the resistance is measured as 19 Ω. The temperature of the windings will now be:

16.  The temperature coefficient of resistance is defined as the change in:

17.  The above formula can be used to determine the resistance of a conductor using the temperature coefficient of resistance method. In the formula the term R_{1} stands for the:

18.  If copper conductor has a resistance of 15 Ω at 0ºC, then using the temperature coefficient of resistance method (Note: Consider the temperature coefficient of resistance of copper to be 0.004 27 Ω/Ω/ºC at 0°C.), its resistance at 20ºC will be:

19.  The supply to a 15A airconditioning unit consists of copper conductors with a crosssectional area of 2.5 mm^{2} and a total resistance of 0.38 Ω. When the airconditioner is operating, the power lost in the conductors will be:

20.  Many materials produce an effect known as ‘superconductivity’ when they are cooled below a certain temperature. At the critical temperature:

21.  When current flows through a conductor, the conductor will heat up. If the conductor temperature exceeds the insulation rating of the cable then the:

22.  A resistance of 120 Ω is required to carry 200 mA of current. The value of power dissipation required by this resistor is:

23.  Smaller value resistors, from 5 watts to several hundred watts, are commonly:

24.  The E12 range of preferred values of resistors is based on a tolerance of:

25.  Look at the following diagram: The size of the above resistor is:

26.  Look at the following diagram: The above diagram shows the characteristic for a typical PTC thermistor. For an increase in temperature, the resistance of the thermistor will:

27.  Look at the following diagram: The above diagram shows the characteristic for a typical NTC thermistor. For an increase in temperature between 50°C and 60°C, the resistance of the thermistor:

28.  The voltage dependent resistor normally only conducts when the:

29.  Lightdependent resistors are used to detect light levels such as in PE (photoelectric) cells on power poles to turn street lights on and off, or to control other night lighting. When light falls on the resistor:

30.  Liquid resistors are often used in motor starters. One advantage of liquid resistance is that the resistance value:

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