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1 | |
The electromotive force is a force exerted on an electric charge to keep it moving. |
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| | A) | True |
| | B) | False |
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2 | |
The direction of conventional current for a conductor is opposite to the direction of electron flow. |
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| | A) | True |
| | B) | False |
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3 | |
Electric current is also a measure of the average speed with which electrons move in a conductor. |
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| | A) | True |
| | B) | False |
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4 | |
According to Ohm’s law, the electric current is inversely proportional to the applied voltage. |
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| | A) | True |
| | B) | False |
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5 | |
Electric resistance increases with an increase in the cross-sectional area of a conductor. |
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| | A) | True |
| | B) | False |
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6 | |
The resistivity of a wire is independent of the length of the wire. |
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| | A) | True |
| | B) | False |
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7 | |
A wire with a diameter of 0.002 in. has a cross-sectional area of 4 cmils. |
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| | A) | True |
| | B) | False |
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8 | |
The temperature coefficient of resistance is equal to the change in resistance per degree change in temperature. |
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| | A) | True |
| | B) | False |
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9 | |
The power loss in a wire is quadrupled if the current is doubled. |
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| | A) | True |
| | B) | False |
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10 | |
A rheostat is a meter that indicates the electric resistance in a circuit. |
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| | A) | True |
| | B) | False |
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11 | |
A unit of electromotive force is the |
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| | A) | joule |
| | B) | newton |
| | C) | volt |
| | D) | watt |
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12 | |
If one were to use a water analogy to study electric current, voltage would be most similar to |
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| | A) | force |
| | B) | pressure |
| | C) | rate of flow |
| | D) | density |
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13 | |
The resistance of a wire is not dependent on its |
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| | A) | temperature |
| | B) | length |
| | C) | area |
| | D) | current |
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14 | |
Which of the following is not a measure of electric power? |
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| | A) | VR² |
| | B) | VI |
| | C) | I²R |
| | D) | V²/R |
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15 | |
Which of the following is not a unit resistivity? |
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| | A) | Ω * cm |
| | B) | Ω * cmil/ft |
| | C) | Ω/ft |
| | D) | Ω * m |
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16 | |
The potential difference between the terminals of a small heater is 60 V. If the resistance of the heater is 30 Ω, the current is |
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| | A) | 0.5 A |
| | B) | 2 A |
| | C) | 1800 A |
| | D) | 3 A |
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17 | |
An emf of 12 V will move 6.25 X 1018 electrons past a given point in 2 s. The resistance is |
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| | A) | 24 Ω |
| | B) | 121 Ω |
| | C) | 6 Ω |
| | D) | 3.84 Ω |
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18 | |
A 120-V heater has a resistance of 600 Ω. The heat energy generated in 1 min is |
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| | A) | 24 J |
| | B) | 120 J |
| | C) | 1200 J |
| | D) | 1440 J |
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19 | |
An aluminum wire has a resistivity of 17 Ω*cmils/ft and a cross-sectional diameter of 0.2 in. What length of this wire is needed to construct a 1700-Ω resistor? |
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| | A) | 200 ft |
| | B) | 144.5 ft |
| | C) | 4 X 106 ft |
| | D) | 2 X 104 ft |
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20 | |
The temperature coefficient of resistance for copper is 0.004/C°. If the resistance of a copper wire is 12 Ω at 20°C, its resistance at 100°C will be |
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| | A) | 3.8 Ω |
| | B) | 13 Ω |
| | C) | 15.84 Ω |
| | D) | 50.4 Ω |
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21 | |
A source of emf of one will perform one of on each coulomb of
charge that passes through it. |
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22 | |
The current in a resistor is directly proportional to the and inversely proportional to the . This is a statement of . |
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23 | |
Four factors that affect the resistance of a wire are , , , and . |
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24 | |
The temperature coefficient of resistance is the change in per unit per unit change in . |
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25 | |
The rate of heat loss in a wire can be found from the product of the and the square of the . |
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26 | |
The direction of conventional current is always the same as the direction in which would move. |
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27 | |
The area of a wire in equals the square of the in mils. |
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28 | |
The resistance of a conductor at a given temperature is directly proportional to its , inversely proportional to its , and dependent on a material constant called its . |
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29 | |
Three laboratory devices used to study resistance, current, and voltage are , , and respectively. |
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30 | |
A source of electromotive force can convert energy to energy. |
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