Physics Physics Practice Problems Solutions Library

Power in Circuits Solutions Library

Access 63 Power in Circuits video and text solutions to help you complete your homework. Need to revisit the concept? Watch our Power in Circuits learn videos.

Browse Solutions

63 solutions

Power in Circuits

Q. How much power is dissipated by each resistor in the figure below, in which V = 9 V and R2 = 15 Ω?

Solved • Mar 30, 2021

Power in Circuits

Q. Consider the three circuits shown above. All the resistors and all the batteries are identical. (select true or false)a. The total power dissipated...

Solved • Feb 11, 2021

Power in Circuits

Q. The power needed for a device drawing 0.8 Amps when connected to 120 V is a. 15 W b. 120 W c. 60 W d. 12 W e. 96 W

Solved • Feb 3, 2021

Power in Circuits

Q. When one light bulb in a string of old Christmas lights burns out, all of the other lights go dark also. This is because the lights are wired in a....

Solved • Feb 3, 2021

Power in Circuits

Q. The current drawn by a 1200-W toaster connected to 120 V is 10 Amps. The resistance of the toaster coils is a. 18 ohms b. 12 ohms c. 6 ohms d. None...

Solved • Feb 3, 2021

Power in Circuits

Q. How much energy does a heater use if it runs for 10 minutes when connected to a 120 Volt outlet drawing 10 Amps of current? a. 12 joules b. 1200 jo...

Solved • Feb 3, 2021

Power in Circuits

Q. In the circuit of the figure (Figure 1), each resistor represents a light bulb. Let R1 = R2 = R3 = R4 = 4.43 Ω and let the EMF be 9.01 V. a. Find t...

Solved • Feb 2, 2021

Power in Circuits

Q. Find the power dissipated in each of these extension cords:(a) an extension cord having a 0.0600 - Ω resistance and through which 5.00 A is flowing...

Solved • Jan 27, 2021

Power in Circuits

Q. The circuit shown has four identical light bulbs and an ideal batterya. Rank the brightness of the bulbs. Explain your reasoning.b. A wire is now a...

Solved • Jan 27, 2021

Power in Circuits

Q. A standard 100 W (120 V) lightbulb contains a 9.40 cm-long tungsten filament. The high-temperature resistivity of tungsten is 9.0 × 10-7Om. What is...

Solved • Jan 17, 2021

Power in Circuits

Q. If you use an extension cord, current travels from the 120 V outlet, along one wire inside the cord, through the appliance you've plugged into the ...

Solved • Jan 17, 2021

Power in Circuits

Q. A 60 W lightbulb and a 100 W lightbulb are placed in the circuit shown in (Figure 1). Both bulbs are glowing. Part A. Which bulb is brighter?A. The...

Solved • Dec 4, 2020

Power in Circuits

Q. 1. The circuit in Figure Q23.4 has two resistors, with R1 > R2. Which resistor dissipates the larger amount of power? Explain.2. The circuit in ...

Solved • Nov 3, 2020

Power in Circuits

Q. A battery has an EMF of 12.0 volts and internal resistance of 3 ohms A 21.0-ohm resistor is connected to the battery. 0.5 Amps flow through the bat...

Solved • Sep 30, 2020

Power in Circuits

Q. A real battery is not just an emf. We can model a real 1.5 V battery as a 1.5 V emf in series with a resistor known as the "internal resistance", a...

Solved • Sep 30, 2020

Power in Circuits

Q. A. How much voltage does the light bulb uses up? How do you measure this value?B. What is the change in the potential energy of a single electron a...

Solved • Sep 22, 2020

Power in Circuits

Q. A) Determine the resistance of a 250-W lightbulb connected to its proper source voltage of 110 V.B) Determine the current through a 250-W lightbulb...

Solved • Aug 19, 2020

Power in Circuits

Q. The lightbulbs in the circuits below are identical with the same resistance R. Which circuit produces more light? (brightness ⇐ ⇒ power)a) circuit ...

Solved • Aug 14, 2020

Power in Circuits

Q. An automobile starter motor has an equivalent resistance of 0.0500 Ω and is supplied by a 12.0-V battery with a 0.0100-Ω internal resistance. If th...

Solved • Aug 2, 2020

Power in Circuits

Q. A circuit maintains a constant resistance. If the current in the circuit is doubled, what is the effect on the power dissipated by the circuit?Sele...

Solved • Jul 30, 2020

Power in Circuits

Q. A constant voltage is applied across a circuit. If the resistance in the circuit is doubled, what is the effect on the power dissipated by the circ...

Solved • Jul 30, 2020

Power in Circuits

Q. An automobile starter motor has an equivalent resistance of 0.0500 Ω and is supplied by a 12.0-V battery with a 0.0100-Ω internal resistance. (a) W...

Solved • Jul 20, 2020

Power in Circuits

Q. Learning Goal: To understand how to compute power dissipation in a resistive circuit.(Figure 1) The circuit in the diagram consists of a battery wi...

Solved • Jul 16, 2020

Power in Circuits

Q. A circuit consisting of 5 resistors is shown in the graph. Their resistances are R1 = 17 Ω, R2 = 35 Ω, R3 = 86 Ω, R4 = 32 Ω, and R5 = 29 Ω, and the...

Solved • Jul 16, 2020

Power in Circuits

Q. Consider a 120 V AC microwave oven that draws 12.5 A.(Randomized Variables I = 12.5 A)What is the maximum instantaneous power consumption, in kilow...

Solved • Jul 15, 2020

Power in Circuits

Q. To understand how to compute power dissipation in a resistive circuit.(Figure 1) The circuit in the diagram consists of a battery with EMF E, a res...

Solved • Jul 15, 2020

Power in Circuits

Q. A 1.5 V battery provides 0.54 A of current.a) At what rate (C/s) is charge lifted by the charge escalator?b) How much work does the charge escalato...

Solved • Jul 15, 2020

Power in Circuits

Q. A car battery with a 12-V emf and an internal resistance of 0.050 Ω is being charged with a current of 60 A. Note that in this process, the battery...

Solved • Jul 15, 2020

Power in Circuits

Q. Determine the power dissipated by the 40 ohm resistor in the circuit shown. (the values from left to right at 4.0 ohm, 40 ohm, 10 ohm, 18V)Possible...

Solved • Jul 14, 2020

Power in Circuits

Q. Part A: How much power is dissipated by the 12 ohms resistor in the figure? in watts pleasePart B: How much power is dissipated by the 15 ohms resi...

Solved • Jul 14, 2020

Power in Circuits

Q. A) Determine the resistance of a 75-W lightbulb connected to its proper source voltage of 110 V.B) Determine the current through a 75-W lightbulb c...

Solved • Jul 14, 2020

Power in Circuits

Q. The graph in the figure shows the current through a 2.0 ohm resistor as a function of time.What was the total energy dissipated by the resistor dur...

Solved • Jul 13, 2020

Power in Circuits

Q. A 100 W lightbulb is brighter than a 60 W lightbulb when both operate at the same voltage of 120 V. If, instead, they were both operated at the sam...

Solved • Jul 13, 2020

Power in Circuits

Q. When running on its 11.4 V battery, a laptop computer uses 8.3 W. The computer can run on battery power for 8.0 h before the battery is depleted.a)...

Solved • Jul 13, 2020

Power in Circuits

Q. The power dissipated in a resistor can be written as _____.A. (ΔVR)2/RB. IΔVRC. I2RD. All of the listed answers are correct.E. None of the listed a...

Solved • Jul 13, 2020

Power in Circuits

Q. The five identical bulbs in the following figure are all glowing. The battery is ideal.What is the order of brightness of the bulbs, from brightest...

Solved • Jul 13, 2020

Power in Circuits

Q. If the battery in (Figure 1) were ideal, lightbulb A would not dim when the switch is closed. However, real batteries have a small internal resista...

Solved • Jul 1, 2020

Power in Circuits

Q. A 1500-W heater is connected to a 120-V line for 2.0 hours. How much heat energy is produced?A) 1.5 kJ B) 11 MJ C) 0.18 MJ D) 3.0 kJ

Solved • Jun 2, 2020

Power in Circuits

Q. In this problem you will derive two different formulas for the power delivered to a resistor.What is the power P supplied to a resistor whose resis...

Solved • Jun 2, 2020

Power in Circuits

Q. Two light bulbs use 30 W and 60 W, respectively, when connected in parallel to a 120-V source. How much power does each bulb use when connected in ...

Solved • Jun 2, 2020

Power in Circuits

Q. As more resistors are added in parallel across a constant voltage source, the power supplied by the source.A. increases.B. decreases.C. does not ch...

Solved • May 21, 2020

Power in Circuits

Q. Consider the circuit of the figure (Figure 1) .(a) What is the total rate at which electrical energy is dissipated in the 5.0-Ω resistor? Express y...

Solved • May 21, 2020

Power in Circuits

Q. The five identical bulbs in the following figure are all glowing. The battery is idealWhat is the order of brightness of the bulbs, from brightest ...

Solved • May 20, 2020

Power in Circuits

Q. A single resistor is wired to a battery as shown in the diagram below.(Figure 1) Define the total power dissipated by this circuit as P0.Now, a sec...

Solved • May 13, 2020

Power in Circuits

Q. Which has a larger resistance, a 60 watt lightbulb or a 100 watt lightbulb ?

Solved • May 11, 2020

Power in Circuits

Q. a) A 60 W light bulb is plugged into a standard 120 V outlet. How much does it cost per 30-day month to leave the light turned on continuously? Ass...

Solved • Apr 30, 2020

Power in Circuits

Q. The heating element of an electric dryer is rated at 4.1 kW when connected to a 240 V line. (a) What is the current in the heating element? Is 12-g...

Solved • Apr 28, 2020

Power in Circuits

Q. A heart dysfunction that can cause death is ventricular fibrillation. This is an uncoordinated quivering of the heart as opposed to regular beating...

Solved • Apr 24, 2020

Power in Circuits

Q. Two light bulbs have resistances of 400 Ω and 800 ΩPart AThe two light bulbs are connected in series across a 120- V line. Find the current through...

Solved • Apr 22, 2020

Power in Circuits

Q. A typical American family uses 1000 kWh of electricity a month.(a) What is the average current in the 120 V power line to the house?(b) On average,...

Solved • Apr 21, 2020

Power in Circuits

Q. A 60-cm-long heating wire is connected to a 120 V outlet. If the wire dissipates 45 W, what are (a) the current in and (b) the resistance of the wire?

Solved • Apr 21, 2020

Power in Circuits

Q. The circuit below has two resistors, with R1 > R2. Which of the two resistors dissipates the larger amount of power?

Solved • Apr 9, 2020

Power in Circuits

Q. For the circuit in the figurea) Find the rate of conversion of internal (chemical) energy to electrical energy within the battery.b) Find the rate ...

Solved • Apr 9, 2020

Power in Circuits

Q. The power rating on a light bulb indicates how much power it would dissipate when it is hooked up to the standard household voltage of 120 V (this ...

Solved • Apr 7, 2020

Power in Circuits

Q. A 1500-W heater is designed to be plugged into a 120-V outlet.(a) What current will flow through the heating coil when the heater is plugged in?(b)...

Solved • Mar 18, 2020

Power in Circuits

Q. A car's battery produces 12 V and has a charge of 70 A*hr. How long could the battery run a car whose entire electronic system had an equivalent re...

Solved • Mar 1, 2017

Power in Circuits

Q. For most materials, the resistance is actually temperature dependent, and typically increases as temperature rises. For this problem, however, let'...

Solved • Mar 1, 2017

Power in Circuits

Q. A 1500 W hair dyer is designed to be used with an electrical outlet that provides 115 V. What current does the hair dryer draw from the outlet? a....

Solved • Feb 28, 2017

Power in Circuits

Q. The resistivity of gold is 2.44 x 10 -8 Ω•m at a temperature of 20°C. A gold wire, 1.4 mm in diameter and 17 cm long, carries a current of 190 ma. ...

Solved • Jan 10, 2017

Power in Circuits

Q. The resistivity of gold is 2.44 x 10 -8 Ω•m at a temperature of 20°C. A gold wire, 1.8 mm in diameter and 14 cm long, carries a current of 480 ma. ...

Solved • Jan 10, 2017

Power in Circuits

Q. Which bulb will be the brightest if connected in series? The voltages and wattages shown in the graphs are their nominal settings, not actual value...

Solved • Jan 9, 2017

Power in Circuits

Q. Four identical resistors are connected in series to an ideal battery. The total power supplied by the battery is 10 W. The same resistors are then ...

Solved • Dec 22, 2016

Power in Circuits

Q. A 200-W light bulb is connected across 110 V. What current will flow through this bulb? A) 0.9 A B) 0 A C) 0.6 A D) 1.8 A

Solved • Dec 19, 2016