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30 Cards in this Set
- Front
- Back
a difference between electric and forces and gravitational forces are not effected by |
repulsive interaction |
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if you strip electrons from an atom, the atom becomes a |
positive ion |
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A sphere has a negative charge of 6.4 x 10-7 coulomb. The approximate number of electrons that must be removed to make the sphere neutral is |
4.0x10^12 |
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The current through a 10-ohm resistor connected to a 120-V power supply is |
12 amps |
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A power line with a resistance of 2 ohms has a current of 80 A in it. The power dissipated in the line is 320 W. |
12,800 W. |
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Which statement is correct? Voltage flows through an open or a closed circuit. Resistance flows through an open circuit. Current is the primary cause of voltage. Charge flows in a closed circuit. All of these are correct. |
charge flows through a closed circuit |
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Voltage can be induced in a wire by moving a magnet near the wire. moving the wire near a magnet. changing the current in a nearby wire. Choices A, B, and C are all true. None of the above choices is true. |
Moving a magnet near the wire moving the wire near a magnet changing the current in a nearby wire |
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A steady current of 2.5 A flows in a wire for 4.0 minutes. How much charge passed through any point in the circuit? |
600 C |
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How long will it take for a charge to pass through a circuit that has a 4.5 A flow and a charge of 2000 C? |
7.5 min |
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An electrical insulator has |
electrons tightly bound to its atoms |
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If you know the power rating of an appliance and voltage of the line it is attached to, you can calculate the current the appliance uses by |
dividing the voltage by power |
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Which of the following would reduce the resistance of a metal wire? |
increasing its thickness |
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An ampere (amp) of current is defined as a coulomb (C) of charge flowing past a point in one second. One electron has a charge of 1.6 x 10-19 C. How many electrons are needed for a coulomb of charge? |
6.25 x 10^18 |
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One volt is |
1 joule/coulomb |
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How much energy is given to one coulomb of charge that flows through a 1.5 volt battery? |
1.5 joules |
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Which of the following statements describes the interaction between magnetic poles? |
like poles repel eachother, and opposites poles attract each other |
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What creates a magnetic field? |
moving electric charges |
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An electronic device that acts as a "one way valve" to allow electrons to flow in one direction only is referred to as a(an) |
Diode |
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Three 10 ohm resistors are connected in parallel to a 12 V battery. The total current in the circuit is |
3.6 amps 30x12 |
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Three 10 ohm resistors are connected in series to a 12 V battery. The total current in the circuit is |
0.4 amps 12/30 |
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Three 10 ohm resistors are connected in parallel to a 12 V battery. The power dissipated by each resistor in the circuit is |
14.4 watts (12\10 =1.2) (1.2x10) |
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Three 10 ohm resistors are connected in series to a 12 V battery. The power dissipated by each resistor in the circuit is |
1.6 Watts 12/30 = .4^2x10 |
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The net charge on a charged capacitor depends on the distance between the capacitor plates. the area of the capacitor plates. the medium between the capacitor plates. All of the above choices are correct. None of the above choices are correct; the net charge is zero |
none of these, the net charge is 0 |
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At $0.10 (10 cents) per kilowatt hour, how much does it cost to operate a 1200 watt hair dryer for one hour |
$0.12 move decimal of wattage |
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You can touch a 100,000-volt Van de Graaff generator with little harm because although the voltage is high, the relatively small amount of charge means there is a relatively small amount of |
energy |
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a kilowatt hour is a unit of |
energy |
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A device that changes mechanical energy to electrical energy by rotating a coil of wire through a magnet field is called a(an) transformer. |
generator |
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How are fossil fuels used to generate electrical energy? |
heat from burning fuel creates steam that spins a turbine |
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Which force field can accelerate an electron, but never change its speed |
magnetic field |
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The voltage across the input terminals of a transformer is 110 V. The primary has 50 loops and the secondary has 25 loops. The voltage the transformer puts out is |
55V |