Exam 26: Dc Circuits

A small galvanometer coil of resistance R = 20 Ω and full-scale deflection at 1 mA is connected in series with a 4980 Ω resistance to build an analog voltmeter. What is the maximum voltage that this voltmeter can read?

A 4.0-μF capacitor is charged to 6.0-V. It is then connected in series with a 3.0-MΩ resistor and connected to a 12-V battery. How long after being connected to the battery will the voltage across the capacitor be 9.0 V?

FIGURE 26-8 -For the circuit shown in Fig. 26-8, which equation is correct for loop2 (going clockwise)?

An analog ammeter able to have a 0.5 A maximum reading is to be built using a small coil of resistance R = 20 Ω, and full scale deflection at 1 mA. What resistance should be added to this coil and how should it be connected to the coil?

Four equal resistors connected across a DC voltage source in either series or parallel will have equal voltage drops across each resistor.

FIGURE 26-1 -Fig. 26-1 shows three identical lightbulbs connected to a battery. What happens to the brightness of lightbulb 1 when the switch S is closed?

Four unequal resistors are connected in a series circuit. Which one of the following statements is correct about this circuit?

A 6-Ω resistor, an 8-Ω resistor, and a 24-Ω resistor are connected together. What is the minimum resistance that can be produced using all three resistors?

FIGURE 26-16 -A 100 V DC signal is applied to four resistors as shown in Fig. 26-16. The values of the resistors are 20 Ω, 40 Ω, 60 Ω, and 80 Ω. What is the voltage across the 40 Ω resistor?

In order to construct a voltmeter from a galvanometer, one normally would

As more resistors are added in series to a constant voltage source, the power supplied by the source

The potential difference between the terminals of a battery, when current flows to an external circuit, is referred to as the

An ideal voltmeter is one that does not change the behavior of a circuit when it is properly used to measure potential difference. The internal resistance of such a meter is

The electromotive force of a battery is the maximum potential difference between the terminals of the battery.

Kirchhoff's junction rule is a statement of

A 2.0-μF capacitor is charged to 12 V and then discharged through a 4.0 × 10⁶ Ω resistor. How long will it take for the voltage across the capacitor to drop to 3.0 V?

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?

FIGURE 26-29 -In Fig. 26-29, I = 0.5 A and R = 12 Ω. What is the value of the emf E?

An RC circuit is connected across a DC voltage source through an open switch. As soon as the switch is closed, the capacitor charges linearly as a function of time.

FIGURE 26-24 -Four resistors of values 2 Ω, 4 Ω, 3 Ω, and 9 Ω are connected across an 8-V DC source as shown in Fig. 26-24. What is the current through the 9-Ω resistor?