physics 19 study guide concepts
A galvanometer can be converted to an ammeter by the addition of a A) small resistance in parallel. B) large resistance in parallel. C) small resistance in series. D) large resistance in series.
a
A voltage reading is obtained by placing a voltmeter across a resistor. What happens to the total current flowing in the circuit as a result of this action? A) The current increases. B) The current decreases. C) The current does not change. D) The current increases if the meter's internal resistance is less than the original resistance in the circuit and decreases if its internal resistance is greater than the circuit's original resistance.
a
An unknown resistor is wired in series with an ammeter, and a voltmeter is placed in parallel across the resistor only. This network is then connected to a battery. If one computes the value of the resistance by dividing the voltmeter reading by the ammeter reading, the value obtained A) is less than the true resistance. B) is greater than the true resistance. C) is the true resistance. D) could be any of the given answers. It depends on other factors.
a
As more and more capacitors are connected in parallel, the equivalent capacitance of the combination increases. A) always true B) Sometimes true; it depends on the voltage of the battery to which the combination is connected. C) Sometimes true; it goes up only if the next capacitor is larger than the average of the existing combination. D) never true
a
As more resistors are added in parallel to a constant voltage source, the power supplied by the source A) increases. B) decreases. C) does not change. D) increases for a time and then starts to decrease.
a
Decreasing the resistance of an ammeter's shunt resistance A) allows it to measure a larger current at full scale deflection. B) allows it to measure a smaller current at full scale deflection. C) enables more current to pass directly through the galvanometer. D) converts it to a voltmeter.
a
If you connect two identical storage batteries together in series ("+" to "-" to "-" to "+"), and place them in a circuit, the combination will provide A) zero volts. B) twice the voltage, and different currents will flow through each. C) twice the voltage, and the same current will flow through each. D) the same voltage, and different currents will flow through each.
a
Increasing the resistance of a voltmeter's series resistance A) allows it to measure a larger voltage at full-scale deflection. B) allows it to measure a smaller voltage at full-scale deflection. C) enables more current to pass through the meter movement at full-scale deflection. D) converts it to an ammeter.
a
Kirchhoff's loop rule is an example of A) conservation of energy. B) conservation of charge. C) conservation of momentum. D) none of the given answers
a
The lamps in a string of Christmas tree lights are connected in parallel. What happens if one lamp burns out? (Assume negligible resistance in the wires leading to the lamps.) A) The brightness of the lamps will not change appreciably. B) The other lamps get brighter equally. C) The other lamps get brighter, but some get brighter than others. D) The other lamps get dimmer equally.E) The other lamps get dimmer, but some get dimmer than others.
a
The potential difference between the terminals of a battery, when no current flows to an external circuit, is referred to as the A) emf.B) terminal voltage.
a
Three identical resistors are connected in series to a battery. If the current of 12 A flows from the battery, how much current flows through any one of the resistors? A) 12 A B) 4 A C) 36 A D) zero
a
When two or more capacitors are connected in parallel to a battery, A) the voltage across each capacitor is the same. B) each capacitor carries the same amount of charge. C) the equivalent capacitance of the combination is less than the capacitance of any one of the capacitors. D) all of the given answers
a
An ideal ammeter should A) have a high coil resistance. B) introduce a very small series resistance into the circuit whose current is to be measured. C) introduce a very large series resistance into the circuit whose current is to be measured. D) consist of a galvanometer in series with a large resistor.
b
An unknown resistor is wired in series with an ammeter, and a voltmeter is placed in parallel across both the resistor and the ammeter. This network is then placed across a battery. If one computes the value of the resistance by dividing the voltmeter reading by the ammeter reading, the value obtained A) is less than the true resistance. B) is greater than the true resistance. C) is the true resistance. D) could be any of the given answers. It depends on other factors
b
As more resistors are added in series to a constant voltage source, the power supplied by the source A) increases. B) decreases. C) does not change. D) increases for a time and then starts to decrease.
b
Consider three identical resistors, each of resistance R. The maximum power each can dissipate is P. Two of the resistors are connected in series, and a third is connected in parallel with these two. What is the maximum power this network can dissipate? A) 2P/3 B) 3P/2 C) 2P D) 3P
b
Kirchhoff's junction rule is an example of A) conservation of energy. B) conservation of charge. C) conservation of momentum. D) none of the given answers
b
The potential difference between the terminals of a battery, when current flows to an external circuit, is referred to as the A) emf.B) terminal voltage.
b
Three identical capacitors are connected in series to a battery. If a total charge of Q flows from the battery, how much charge does each capacitor carry? A) 3Q B) Q C) Q/3 D) Q/9
b
Three identical resistors are connected in parallel to a 12-V battery. What is the voltage of any one of the resistors? A) 36 V B) 12 V C) 4 V D) zero
b
Three identical resistors are connected in parallel to a battery. If the current of 12 A flows from the battery, how much current flows through any one of the resistors? A) 12 A B) 4 A C) 36 A D) zero
b
When resistors are connected in parallel, we can be certain that A) the same current flows in each one. B) the potential difference across each is the same. C) the power dissipated in each is the same. D) their equivalent resistance is greater than the resistance of any one of the individual resistances.
b
A current reading is obtained by properly placing an ammeter in a circuit consisting of one resistor and one battery. As a result, A) the voltage drop across the resistor increases. B) the current flowing in the circuit increases. C) the current flowing in the circuit decreases. D) the current flowing in the circuit does not change.
c
A resistor and a capacitor are connected in series to an ideal battery of constant terminal voltage. At the moment contact is made with the battery, the voltage across the capacitor is A) greater than the battery's terminal voltage. B) less than the battery's terminal voltage, but greater than zero. C) equal to the battery's terminal voltage. D) zero.
c
A resistor and a capacitor are connected in series to an ideal battery of constant terminal voltage. At the moment contact is made with the battery, the voltage across the resistor is A) greater than the battery's terminal voltage. B) less than the battery's terminal voltage, but greater than zero. C) equal to the battery's terminal voltage. D) zero.
c
If you connect two identical storage batteries together in parallel, and place them in a circuit, the combination will provide A) twice the voltage and twice the total charge that one battery would. B) twice the voltage and the same total charge that one battery would. C) the same voltage and twice the total charge that one battery would. D) half the voltage and half the total charge that one battery would.
c
If you connect two identical storage batteries together in series ("+" to "-" to "+" to "-"), and place them in a circuit, the combination will provide A) zero volts. B) twice the voltage, and different currents will flow through each. C) twice the voltage, and the same current will flow through each. D) the same voltage, and different currents will flow through each.
c
Three identical capacitors are connected in parallel to a battery. If a total charge of Q flows from the battery, how much charge does each capacitor carry? A) 3Q B) Q C) Q/3 D) Q/9
c
Three identical resistors are connected in series to a 12-V battery. What is the voltage across any one of the resistors? A) 36 V B) 12 V C) 4 V D) zero
c
What is the unit for the quantity RC? A) ohms B) volt-ampere/ohm C) seconds D) meters
c
When resistors are connected in series, A) the same power is dissipated in each one. B) the potential difference across each is the same. C) the current flowing in each is the same. D) More than one of the given answers is true.
c
A resistor and a capacitor are connected in series to an ideal battery of constant terminal voltage. When this system reaches its steady-state, the voltage across the resistor is A) greater than the battery's terminal voltage. B) less than the battery's terminal voltage, but greater than zero. C) equal to the battery's terminal voltage. D) zero.
d
As more and more capacitors are connected in series, the equivalent capacitance of the combination increases. A) always true B) Sometimes true; it depends on the voltage of the battery to which the combination is connected. C) Sometimes true; it goes up only if the next capacitor is larger than the average of the existing combination. D) never true
d
In order to construct a voltmeter from a galvanometer, one normally would A) use a very small shunt resistor. B) use a very large shunt resistor. C) use a very small series resistor. D) use a very large series resistor.
d
When two or more capacitors are connected in series to a battery, A) the total voltage across the combination is the algebraic sum of the voltages across the individual capacitors. B) each capacitor carries the same amount of charge. C) the equivalent capacitance of the combination is less than the capacitance of any of the capacitors. D) all of the given answers
d
When two or more resistors are connected in parallel to a battery, A) the voltage across each resistor is the same. B) the total current flowing from the battery equals the sum of the currents flowing through each resistor. C) the equivalent resistance of the combination is less than the resistance of any one of the resistors. D) all of the given answers
d
When two or more resistors are connected in series to a battery A) the total voltage across the combination is the algebraic sum of the voltages across the individual resistors. B) the same current flows through each resistor. C) the equivalent resistance of the combination is equal to the sum of the resistances of each resistor. D) all of the given answers
d
Which of the equations here is valid for the circuit shown? FIGURE 19-1 A) 2 - I1 - 2I2 = 0 B) 2 - 2I1 - 2I2 - 4I3 = 0 C) 4 - I1 + 4I3 = 0 D) -2 - I1 - 2I2 = 0 E) 6 - I1 - 2I2 = 0
d
You obtain a 100-W light bulb and a 50-W light bulb. Instead of connecting them in the normal way, you devise a circuit that places them in series across normal household voltage. Which statement is correct? A) Both bulbs glow at the same reduced brightness. B) Both bulbs glow at the same increased brightness. C) The 100-W bulb glows brighter than the 50-W bulb. D) The 50-W bulb glows more brightly than the 100-W bulb.
d
