Exam 23: Circuits

A network of capacitors is connected across a potential difference V₀ as shown in the figure. (a)What should V₀ be so that the 60.0-µF capacitor will have 18.0 µC of charge on each of its plates? (b)Under the conditions of part (a), how much total energy is stored in this network of capacitors?

Three light bulbs, A, B, and C, have electrical ratings as follows: Bulb A: 96.0 W, 1.70 A Bulb B: 80.0 V, 205 W Bulb C: 120 V, 0.400 A These three bulbs are connected in a circuit across a 150-V voltage power source, as shown in the figure. Assume that the filament resistances of the light bulbs are constant and independent of operating conditions. What is the equivalent resistance of this combination of bulbs between the terminals of the power source?

A series circuit consists of a 2.5-?F capacitor, a 7.6-M? resistor, and an ideal 6.0-V dc power source. (a)What is the time constant for charging the capacitor? (b)What is the potential difference across the capacitor 25 s after charging begins?

For the circuit shown in the figure, R₁ = 50 ?, R₂ = 20 ?, R₃ = 35 ?, R₄ = 10 ?, R₅ = 68 ?, I₁ = 0.111 A, I₂ = 0.142 A, and the batteries are ideal. (a)Determine V₁ and V₂. (b)What is the potential difference across R₄?

Two capacitors are connected as shown in the figure, with C₁ = 4.0 µF and C₂ = 7.0 µF. If a voltage source V = 90 V is applied across the combination, find the potential difference across C₁.

The network shown is assembled with uncharged capacitors X , Y, and Z, with $C _ { X } = 8 . - \mu F \text {, }$ $\mathrm { C} _ { \mathrm { Y } } = 9 . - \mu \mathrm { F }$ and $C _ { Z } = 1.0 \mu \mathrm { F }$ The switches S₁ and S₂ are initially open, and a potential difference V_ab = 120 V is applied between points a and b. After the network is assembled, switch S₁ is then closed, but switch S₂ is kept open. How much charge is finally stored in capacitor Y?

What different resistances can be obtained by using two 2.0-Ω resistors and one 4.0-Ω resistor? You must use all three of them in each possible combination.

For the circuit shown in the figure, write the Kirchhoff loop equation for the entire outside loop. Notice the directions of the currents!

When an initially uncharged capacitor is charged through a 25-k? resistor by a 75-V dc ideal power source, it takes 0.23 ms for the capacitor to reach 50% of its maximum charge? What is the capacitance of this capacitor?

Two resistors in series are equivalent to 9.0 ?, and in parallel they are equivalent to 2.0 ?. What are the resistances of these two resistors?

A 9.00-µF and a 12.0-µF capacitor are connected together, and this combination is connected across a 25.0-V potential difference. How much electric energy is stored in the combination if they are connected (a)in parallel or (b)in series?

Three resistors of 12 ?, 12 ?, and 6.0 ? are connected together, and an ideal 12-V battery is connected across the combination. What is the current from the battery if they are connected (a)in series or (b)in parallel?

A 2.0-μF capacitor and a 4.0-μF capacitor are connected in series across an 8.0-V potential source. What is the charge on the 2.0-μF capacitor?

What current flows from the battery in the circuit shown in the figure? The battery is ideal, and all the numbers are accurate to two significant figures.

A network of capacitors is mostly inside a sealed box, but one capacitor C_X is sticking out, as shown in the figure. When you connect a multimeter across points a and b, it reads 27.0 µF. What is C_X?

Two resistors with resistances of 5.0 ? and 9.0 ? are connected in parallel. A 4.0-? resistor is then connected in series with this parallel combination. An ideal 6.0-V battery is then connected across the series-parallel combination. What is the current through (a)the 4.0-? resistor and (b)the 5.0-? resistor?

Two 100-W light bulbs of fixed resistance are to be connected to an ideal 120-V source. What are the current, potential difference, and dissipated power for each bulb when they are connected (a)in parallel (the normal arrangement)? (b)in series?

Suppose you have two capacitors and want to use them to store the maximum amount of energy by connecting them across a voltage source. You should connect them

What is the equivalent resistance of the circuit shown in the figure? The battery is ideal and all resistances are accurate to 3 significant figures.

Determine the current in the 4.0-Ω resistor for the circuit shown in the figure. Assume that the batteries are ideal and that all numbers are accurate to two significant figures.