Electric Current Review
Circuit A has four 3.0-ohm resistors connected in series with a 24-volt battery, and circuit B has two 3.0-ohm resistors connected in series with a 24-volt battery. Compared to the total potential drop across circuit A, the total potential drop across circuit B is
the same
Compared to the resistivity of a 0.4-meter length of 1-millimeter diameter copper wire at 0°C, the resistivity of a 0.8-meter length of 1-millimeter-diameter copper wire at 0°C is
the same
48 W
An 18-ohm resistor and a 36-ohm resistor are connected in parallel with a 24-volt battery. A single ammeter is placed in the circuit to read its total current. Calculate the total power dissipated.
4.5 x 10^-3 Ω
An aluminum wire of length 1.0 meter has a resistance of 9.0 × 10^-3 ohm. If the wire were cut into two equal lengths, each length would have a resistance of
Equivalent resistance decreases and total current increases.
As the number of resistors in a parallel circuit is increased, what happens to the equivalent resistance of the circuit and total current in the circuit?
A 2.0-meter length of copper wire is connected across a potential difference of 24 millivolts. The current through the wire is 0.40 ampere. The same copper wire at the same temperature is then connected across a potential difference of 48 millivolts. The current through the wire is
0.80 A
An 18-ohm resistor and a 36-ohm resistor are connected in parallel with a 24-volt battery. A single ammeter is placed in the circuit to read its total current. Calculate the equivalent resistance.
12 Ω
A student constructed a series circuit consisting of a 12.0-volt battery, a 10.0-ohm lamp, and a resistor. The circuit does not contain a voltmeter or an ammeter. When the circuit is operating, the total current through the circuit is 0.50 ampere.
14 Ω
A 100.-ohm resistor and an unknown resistor are connected in series to a 10.0-volt battery. If the potential drop across the 100.-ohm resistor is 4.00 volts, the resistance of the unknown resistor is
150. Ω
A hair dryer with a resistance of 9.6 ohms operates at 120 volts for 2.5 minutes. The total electrical energy used by the dryer during this time interval is
2.3 × 10^5 J
A series circuit has a total resistance of 1.00 × 10^2 ohms and an applied potential difference of 2.00 × 10^2 volts. The amount of charge passing any point in the circuit in 2.00 seconds is
4.00 C
An aluminum wire of length 1.0 meter has a resistance of 9.0 × 10^-3 ohm. If the wire were cut into two equal lengths, each length would have a resistance of
4.5 x 10^-3 Ω
R =5.5 × 10^-2 Ω
A 10.0-meter length of copper wire is at 20°C. The radius of the wire is 1.0 × 10^-3 meter. Calculate the resistance of the wire.
0.10 A
A 12-volt battery causes 0.60 ampere to flow through a circuit that contains a lamp and a resistor connected in parallel. The lamp is operating at 6.0 watts.
2.5 Ω
A combination of two identical resistors connected in series has an equivalent resistance of 10. ohms. What is the equivalent resistance of the combination of these same two resistors when connected in parallel?
14 Ω
A student constructed a series circuit consisting of a 12.0-volt battery, a 10.0-ohm lamp, and a resistor. The circuit does not contain a voltmeter or an ammeter. When the circuit is operating, the total current through the circuit is 0.50 ampere.
24 Ω
A student constructed a series circuit consisting of a 12.0-volt battery, a 10.0-ohm lamp, and a resistor. The circuit does not contain a voltmeter or an ammeter. When the circuit is operating, the total current through the circuit is 0.50 ampere.
in parallel with the circuit resistor
A student uses a voltmeter to measure the potential difference across a circuit resistor. To obtain a correct reading, the student must connect the voltmeter
silver
Copper is a metal commonly used for electrical wiring in houses. Which metal conducts electricity better than copper at 20°C?