HW-08

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HW 08: Power and DC Circuits Due: 11:59pm on Monday, October 17, 2022 You will receive no credit for items you complete after the assignment is due. Grading Policy Kirchhoff's Rules and Applying Them Learning Goal: To understand the origins of both of Kirchhoff's rules and how to use them to solve a circuit problem. This problem introduces Kirchhoff's two rules for circuits: ! Kirchhoff's loop rule : The sum of the voltage changes across the circuit elements forming any closed loop is zero. ! Kirchhoff's junction rule : The algebraic sum of the currents into (or out of) any junction in the circuit is zero. The figure shows a circuit that illustrates the concept of loops , which are colored red and labeled loop 1 and loop 2. Loop 1 is the loop around the entire circuit, whereas loop 2 is the smaller loop on the right. To apply the loop rule you would add the voltage changes of all circuit elements around the chosen loop. The figure contains two junctions (where three or more wires meet)--they are at the ends of the resistor labeled . The battery supplies a constant voltage , and the resistors are labeled with their resistances. The ammeters are ideal meters that read and respectively. The direction of each loop and the direction of each current arrow that you draw on your own circuits are arbitrary. Just assign voltage drops consistently and sum both voltage drops and currents algebraically and you will get correct equations. If the actual current is in the opposite direction from your current arrow, your answer for that current will be negative. The direction of any loop is even less imporant: The equation obtained from a counterclockwise loop is the same as that from a clockwise loop except for a negative sign in front of every term (i.e., an inconsequential change in overall sign of the equation because it equals zero). Part A The junction rule describes the conservation of which quantity? Note that this rule applies only to circuits that are in a steady state. Hint 1. At the junction Think of the analogy with water flow. If a certain amount of water comes to a split in the pipe, what can you say (mathematically) about the sum of the three masses of water at this junction? ANSWER: R 3 V b I 1 I 2 HW 08: Power and DC Circuits https://session.masteringphysics.com/myct/assignmentPrintView?assig... 1 of 25 17/10/22, 8:44 pm

Correct Part B Apply the junction rule to the junction labeled with the number 1 (at the bottom of the resistor of resistance ). Answer in terms of given quantities, together with the meter readings and and the current . Hint 1. Elements in series The current through resistance is not labeled. You should recognize that the current passing through the ammeter also passes through resistance because there is no junction in between the resistor and the ammeter that could allow it to go elsewhere. Similarly, the current passing through the battery must be also. Circuit elements connected in a string like this are said to be in series and the same current must pass through each element. This fact greatly reduces the number of independent current values in any practical circuit. ANSWER: Correct If you apply the juncion rule to the junction above , you should find that the expression you get is equivalent to what you just obtained for the junction labeled 1. Obviously the conservation of charge or current flow enforces the same relationship among the currents when they separate as when they recombine. Part C Apply the loop rule to loop 2 (the smaller loop on the right). Sum the voltage changes across each circuit element around this loop going in the direction of the arrow. Remember that the current meter is ideal. Express the voltage drops in terms of , , , the given resistances, and any other given quantities. Hint 1. Elements in series have same current The current through the ammeter is , and this current has to go through the resistor of resistance because there is no junction in between that could add or subtract current. Similarly, the current passing through the battery must be also. Circuit elements connected in a string like this are said to be in series and the same current must pass through each element. This fact greatly reduces the number of independent current values in any practical circuit. Hint 2. Sign of voltage across resistors In determining the signs, note that if your chosen loop traverses a particular resistor in the same direction as the current through that resistor, then the end it enters through will have a more positive potential than the end from charge voltage resistance R 2 I 1 I 2 I 3 R 1 I 1 R 1 I 1 = Σ I = 0 + − I 2 I 3 I 1 R 2 V b I 2 I 3 I 1 R 1 I 1 HW 08: Power and DC Circuits https://session.masteringphysics.com/myct/assignmentPrintView?assig... 2 of 25 17/10/22, 8:44 pm

which it exits by the amount . Thus the voltage change across that resistor will be negative. Conversely, if your chosen loop traverses the resistor in the opposite direction from its current arrow, the voltage changes across the resistor will be positive. Let these conventions govern your equations (i.e., don't try to figure out the direction of current flow when using the Kirchhoff loop--decide when you put the current arrows on the resistors and stick with that choice). Hint 3. Voltage drop across ammeter An ideal ammeter has zero resistance. Hence there is no voltage drop across it. ANSWER: Correct Part D Now apply the loop rule to loop 1 (the larger loop spanning the entire circuit). Sum the voltage changes across each circuit element around this loop going in the direction of the arrow. Express the voltage drops in terms of , , , the given resistances, and any other given quantities. ANSWER: Correct There is one more loop in this circuit, the inner loop through the battery, both ammeters, and resistors and . If you apply Kirchhoff's loop rule to this additional loop, you will generate an extra equation that is redundant with the other two. In general, you can get enough equations to solve a circuit by either 1. selecting all of the internal loops (loops with no circuit elements inside the loop) or 2. using a number of loops (not necessarily internal) equal to the number of internal loops, with the extra proviso that at least one loop pass through each circuit element. Tactics Box 28.1 Using Kirchhoff's Loop Law Learning Goal: To practice Tactics Box 28.1 Using Kirchhoff's Loop Law. Circuit analysis is based on Kirchhoff's laws, which can be summarized as follows: ! Kirchhoff's junction law says that the total current into a junction must equal the total current leaving the junction. ! Kirchhoff's loop law says that if we add all of the potential differences around the loop formed by a circuit, the sum of these potential differences must be zero. Although Kirchhoff's junction law is needed only when there are one or more junctions in a circuit, Kirchhoff's loop law is used IR = Σ ( Δ V ) = 0 − I 3 R 3 I 2 R 2 V b I 1 I 3 = Σ ( Δ V ) = 0 − − V b I 1 R 1 I 3 R 3 R 1 R 2 HW 08: Power and DC Circuits https://session.masteringphysics.com/myct/assignmentPrintView?assig... 3 of 25 17/10/22, 8:44 pm

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for analyzing any type of circuit, as explained in the following tactics box. TACTICS BOX 28.1 Using Kirchhoff’s loop law 1. Draw a circuit diagram. Label all known and unknown quantities. 2. Assign a direction to the current. Draw and label a current arrow to show your choice. ! If you know the actual current direction, choose that direction. ! If you don't know the actual current direction, make an educated guess. All that will happen if you choose wrong is that your value for will end up negative. 3. "Travel" around the loop. Start at any point in the circuit; then, go all the way around the loop in the direction you assigned to the current in Step 2. As you go through each circuit element, is interpreted to mean . ! For an ideal battery with current in the negative- to-positive direction: . ! For an ideal battery in the positive-to-negative direction (i.e., the current is going into the positive terminal of the battery): . ! For a resistor: . 4. Apply the loop law : . Part A The current in the circuit shown in the figure is 0.20 . What is the potential difference across the battery traveling in the direction shown in ? Express your answer in volts. Hint 1. Find the potential difference across the resistor What is the potential difference across the resistor in the direction assigned to the current in ? Express your answer in volts. I I Δ V Δ V = − V downstream V upstream Δ = + E V bat Δ = − E V bat Δ = − IR V R Σ ( Δ V = 0 ) i A Δ V bat Δ V R HW 08: Power and DC Circuits https://session.masteringphysics.com/myct/assignmentPrintView?assig... 4 of 25 17/10/22, 8:44 pm

ANSWER: ANSWER: Correct Part B Find the current in the circuit shown in . Express your answer in amperes. Hint 1. Find the potential difference across the battery If we assign the counterclockwise direction to the current, what is the potential difference across the battery, ? ANSWER: = -6.0 Δ V R V = 6.0 Δ V bat V I Δ V bat HW 08: Power and DC Circuits https://session.masteringphysics.com/myct/assignmentPrintView?assig... 5 of 25 17/10/22, 8:44 pm

Hint 2. Find the potential difference across the 40-ohm resistor If we assign the counterclockwise direction to the current in the circuit, what is the potential difference across the 40-ohm resistor? Express your answer in terms of the variable . ANSWER: Hint 3. Find the potential difference across the 50-ohm resistor If we assign the counterclockwise direction to the current in the circuit, what is the potential difference across the 50-ohm resistor? Express your answer in terms of the variable . ANSWER: ANSWER: Correct Part C What is the absolute value of the potential difference across the unknown element in the circuit shown in ? Express your answer in volts. Δ = − 9.0 V V bat Δ = +9.0 V V bat Δ = − 4.5 V V bat Δ = +4.5 V V bat I Δ V R1 I = Δ V R1 − 40 I I Δ V R2 I = Δ V R2 − 50 I = 0.10 I A | Δ V | HW 08: Power and DC Circuits https://session.masteringphysics.com/myct/assignmentPrintView?assig... 6 of 25 17/10/22, 8:44 pm

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Hint 1. Apply Kirchhoff's loop law Complete the expression below, and write an equation for Kirchhoff's loop law applied to the circuit in the figure. Express your answer in terms of the variable . ANSWER: ANSWER: Correct Part D Is the unknown element a battery or a resistor? ANSWER: Correct Problem 28.29 - Enhanced - with Hints and Feedback The resistor in is dissipating 40 of power. Δ V = Σ ( Δ V ) i 6 − 4 − 3 + ( Δ ) V = 0 = 1.0 | Δ V | V The unknown element is a battery. The unknown element is a resistor. Whether it is a battery or a resistor cannot be determined. 10 Ω W HW 08: Power and DC Circuits https://session.masteringphysics.com/myct/assignmentPrintView?assig... 7 of 25 17/10/22, 8:44 pm

Part A How much power is the resistor dissipating? Express your answer to two significant figures and include the appropriate units. Hint 1. How to approach the problem Resistors connected in series have the same current. Recall the expression for power in terms of resistance and current to find the current through the 5 resistor. ANSWER: Correct Part B How much power is the resistor dissipating? Express your answer to two significant figures and include the appropriate units. Hint 1. How to approach the problem Use Kirchhoff's loop law to calculate the potential difference across the 20 resistor. Recall the expression for dissipated power in terms of resistance and the potential difference. ANSWER: Correct Problem 28.31 - Enhanced - with Hints and Feedback 5 Ω Ω = 20 P W 20 Ω Ω = 45 P W HW 08: Power and DC Circuits https://session.masteringphysics.com/myct/assignmentPrintView?assig... 8 of 25 17/10/22, 8:44 pm

Part A In , what is the value of the potential at points and ? Express your answers in volts to two significant figures separated by a comma. You did not open hints for this part. ANSWER: Problem 28.38 Part A A multiloop circuit is shown in the figure. It is not necessary to solve the entire circuit. The current 2 is closest to ANSWER: a b , = V a V b V I HW 08: Power and DC Circuits https://session.masteringphysics.com/myct/assignmentPrintView?assig... 9 of 25 17/10/22, 8:44 pm

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Correct Problem 28.42 Part A A multiloop circuit is shown in the figure. Some circuit quantities are not labeled. It is not necessary to solve the entire circuit. The current is closest to ANSWER: Correct 8 A. -6 A. -8 A. 6 A. zero. I 2 -0.3 A. +0.5 A. +0.1 A. -0.1 A. +0.3 A. HW 08: Power and DC Circuits https://session.masteringphysics.com/myct/assignmentPrintView?assig... 10 of 25 17/10/22, 8:44 pm

Problem 28.30 Part A In the following figure, what is the value of the potential at points a and b? Express your answer using two significant figures separated by a comma. ANSWER: Correct Problem 28.65 - Enhanced - with Hints and Feedback A 12 car battery dies not so much because its voltage drops but because chemical reactions increase its internal resistance. A good battery connected with jumper cables can both start the engine and recharge the dead battery. Consider the automotive circuit of . , = 9.0,1.0 V a V b V V HW 08: Power and DC Circuits https://session.masteringphysics.com/myct/assignmentPrintView?assig... 11 of 25 17/10/22, 8:44 pm

Part A How much current could the good battery alone drive through the starter motor? Express your answer with the appropriate units. Hint 1. How to approach the problem Consider the circuit in the figure without the dead battery. Use Ohm's law to calculate the current. ANSWER: Correct Part B How much current is the dead battery alone able to drive through the starter motor? Express your answer with the appropriate units. Hint 1. How to approach the problem Consider the circuit in the figure without the good battery. Use Ohm's law to calculate the current. ANSWER: Correct Part C With the jumper cables attached, how much current passes through the starter motor? Express your answer with the appropriate units. Hint 1. How to approach the problem Consider the circuit shown in the figure. Use Kirchhoff's loop law and Kirchhoff's junction law and solve the equations for the current through the starter motor. ANSWER: = 200 I A = 14.5 I A HW 08: Power and DC Circuits https://session.masteringphysics.com/myct/assignmentPrintView?assig... 12 of 25 17/10/22, 8:44 pm

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Correct Part D With the jumper cables attached, how much current passes through the dead battery? Express your answer with the appropriate units. Hint 1. How to approach the problem Consider the circuit shown in the figure. Use Kirchhoff's loop law and Kirchhoff's junction law and solve the equations for the current through the dead battery. ANSWER: Correct Part E With the jumper cables attached, in which direction current passes through the dead battery? Hint 1. How to approach the problem You had to choose the direction for current to solve the previous part. You can determine whether the actual direction of current matches the chosen direction by looking at the sign of the value you have reached. ANSWER: Correct Problem 28.55 = 200 I A = 3.9 I A downward out of the page upward into the page HW 08: Power and DC Circuits https://session.masteringphysics.com/myct/assignmentPrintView?assig... 13 of 25 17/10/22, 8:44 pm

Part A What is the battery current when the switch in is open? Express your answer with the appropriate units. ANSWER: Correct Part B What is the potential difference between points and when the switch is open? Express your answer with the appropriate units. ANSWER: Correct Part C What is the battery current when the switch is closed? Express your answer with the appropriate units. ANSWER: Correct Part D I bat = 8.0 I bat A Δ V ab a b = 8.0 Δ V ab V I bat = 9.1 I bat A HW 08: Power and DC Circuits https://session.masteringphysics.com/myct/assignmentPrintView?assig... 14 of 25 17/10/22, 8:44 pm

What is the potential difference between points and when the switch is closed? Express your answer as an integer and include the appropriate units. ANSWER: Correct Problem 28.60 For the circuit shown in the figure , find the current through and the potential difference across each resistor. Part A Find the current through each resistor. Enter your answers numerically separated by commas. ANSWER: Correct Part B Find the potential difference across each resistor. Enter your answers numerically separated by commas. ANSWER: Δ V ab a b = 0 Δ V ab V , , , = 2.0,1.5,0.125,0.375 I 3 Ω I 4 Ω I 48 Ω I 16 Ω A HW 08: Power and DC Circuits https://session.masteringphysics.com/myct/assignmentPrintView?assig... 15 of 25 17/10/22, 8:44 pm

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Correct Equivalent Resistance Consider the network of four resistors shown in the diagram, where = 2.00 , = 5.00 , = 1.00 , and = 7.00 . The resistors are connected to a constant voltage of magnitude . Part A Find the equivalent resistance of the resistor network. Express your answer in ohms. Hint 1. How to reduce the network of resistors The network of resistors shown in the diagram is a combination of series and parallel connections. To determine its equivalent resistance, it is most convenient to reduce the network in successive stages. First compute the equivalent resistance of the parallel connection between the resistors and and imagine replacing the connection with a resistor with such resistance. The resulting network will consist of three resistors in series. Then find their equivalent resistance, which will also be the equivalent resistance of the original network. Hint 2. Find the resistance equivalent to and Find the equivalent resistance of the parallel connection between the resistors and . Express your answer in ohms. Hint 1. Two resistors in parallel Consider two resistors of resistance and that are connected in parallel. They are equivalent to a , , , = 6,6,6,6 Δ V 3 Ω Δ V 4 Ω Δ V 48 Ω Δ V 16 Ω V R 1 Ω R 2 Ω R 3 Ω R 4 Ω V R A R 1 R 2 R 1 R 2 R 12 R 1 R 2 R a R b HW 08: Power and DC Circuits https://session.masteringphysics.com/myct/assignmentPrintView?assig... 16 of 25 17/10/22, 8:44 pm

resistor with resistance , which satisfies the following relation: . ANSWER: Correct If you replace the resistors and with an equivalent resistor with resistance , the resulting network will consist of three resistors , and connected in series. Their equivalent resistance is also the equivalent resistance of the original network. Hint 3. Three resistors in series Consider three resistors of resistance , , and that are connected in series. They are equivalent to a resistor with resistance , which is given by . ANSWER: Correct Part B Two resistors of resistance = 3.00 and = 3.00 are added to the network, and an additional resistor of resistance = 3.00 is connected by a switch, as shown in the diagram.. Find the equivalent resistance of the new resistor network when the switch is open. Express your answer in ohms. Hint 1. How to reduce the extended network of resistors Since the switch is open, no current passes through the resistor , which can be ignored then. As you did in R eq = + 1 R eq 1 R a 1 R b = 1.43 R 12 Ω R 1 R 2 R 12 R 12 R 3 R 4 R a R b R c R eq = + + R eq R a R b R c = 9.43 R A Ω R 5 Ω R 6 Ω R 7 Ω R B R 7 HW 08: Power and DC Circuits https://session.masteringphysics.com/myct/assignmentPrintView?assig... 17 of 25 17/10/22, 8:44 pm

Part A, reduce the network in successive stages. Note that the new resistor is in series with the resistors and , while the new resistor is in series with . Hint 2. Find the resistance equivalent to , , and Find the resistance equivalent to the resistor connection with , , and . Express your answer in ohms. Hint 1. Find the resistance equivalent to and Find the resistance equivalent to the connection between and . Express your answer in ohms. Hint 1. Two resistors in series Consider two resistors of resistance , and that are connected in series. They are equivalent to a resistor with resistance , which is given by . ANSWER: Hint 2. Two resistors in parallel Consider two resistors of resistance and that are connected in parallel. They are equivalent to a resistor with resistance , which satisfies the following relation: . ANSWER: All attempts used; correct answer displayed If you replace the resistors , , and with an equivalent resistor with resistance , the resulting network will consist of four resistors— , , , and —all connected in series. Their equivalent resistance is also the equivalent resistance of the original network. Hint 3. Four resistors in series Consider four resistors of resistance , , , and that are connected in series. They are equivalent to a resistor with resistance , which is given by . ANSWER: R 5 R 3 R 4 R 6 R 12 R 1 R 2 R 6 R 126 R 1 R 2 R 6 R 1 R 6 R 16 R 1 R 6 R a R b R eq = + R eq R a R b = 5.00 R 16 Ω R a R b R eq = + 1 R eq 1 R a 1 R b = 2.50 R 126 Ω R 1 R 2 R 6 R 126 R 126 R 3 R 4 R 5 R a R b R c R d R eq = + + + R eq R a R b R c R d HW 08: Power and DC Circuits https://session.masteringphysics.com/myct/assignmentPrintView?assig... 18 of 25 17/10/22, 8:44 pm

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Correct Part C Find the equivalent resistance of the resistor network described in Part B when the switch is closed. Express your answer in ohms. Hint 1. How to reduce the network of resistors when the switch is closed When the switch is closed, current passes through the resistor ; therefore the resistor must be included in the calculation of the equivalent resistance. Also when the switch is closed, the resistor is no longer connected in series with the resistors and , as was the case when the switch was open. Instead, now is in parallel with and their equivalent resistor will be in series with and . Hint 2. Find the resistance equivalent to and Find the equivalent resistance of the parallel connection between the resistors and . Express your answer in ohms. Hint 1. Two resistors in parallel Consider two resistors of resistance and that are connected in parallel. They are equivalent to a resistor with resistance , which satisfies the following relation: . ANSWER: Hint 3. Four resistors in series Consider four resistors of resistance , , , and that are connected in series. They are equivalent to a resistor with resistance , which is given by . ANSWER: Correct = 13.5 R B Ω R C R 7 R 4 R 3 R 5 R 4 R 7 R 3 R 5 Ω Ω R 47 R 4 R 7 R a R b R eq = + 1 R eq 1 R a 1 R b = 2.10 R 47 Ω R a R b R c R d R eq = + + + R eq R a R b R c R d = 8.60 R C Ω HW 08: Power and DC Circuits https://session.masteringphysics.com/myct/assignmentPrintView?assig... 19 of 25 17/10/22, 8:44 pm

Problem 28.62 Part A For the circuit shown in the figure find the current through each resistor. Express your answers using two significant figures. Enter your answers numerically separated by commas. ANSWER: Correct Part B For the circuit shown in the figure find the potential difference across each resistor. Express your answers using two significant figures. Enter your answers numerically separated by commas. ANSWER: Correct Problem 28.39 It seems hard to justify spending 4.00 for a compact fluorescent lightbulb when an ordinary incandescent lightbulb costs 50 . To see if this makes sense, compare a 60 incandescent bulb lasting 1000 to a 15 compact fluorescent bulb having a lifetime of 10,000 . Both bulbs produce the same amount of visible light and are interchangeable. If , , , , = 1.0,0.25,0.75,0.56,0.19 I 3 Ω I 24 Ω I 5 Ω I 4 Ω I 12 Ω A , , , , = 3.0,6.0,3.8,2.3,2.3 Δ V 3 Ω Δ V 24 Ω Δ V 5 Ω Δ V 4 Ω Δ V 12 Ω V $ ¢ W hours W hours HW 08: Power and DC Circuits https://session.masteringphysics.com/myct/assignmentPrintView?assig... 20 of 25 17/10/22, 8:44 pm

electricity costs 0.10 , what is the cost - purchase plus energy - to obtain 10,000 of light from each type of bulb? This is called the life-cycle cost. Part A Life-cyle cost of incandescent blub. ANSWER: Correct Part B Life-cyle cost of fluorescent blub. ANSWER: Correct Conceptual Question 28.07 Part A Two light bulbs, 1 and B 2 , are connected to a battery having appreciable internal resistance as shown in the figure. What happens to the brightness of bulb 1 when we close the switch ? $ /kWh hours = 65 p dollars = 19 p dollars B B S HW 08: Power and DC Circuits https://session.masteringphysics.com/myct/assignmentPrintView?assig... 21 of 25 17/10/22, 8:44 pm

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ANSWER: Correct Conceptual Question 28.03 Part A In the circuit shown in the figure, all the lightbulbs are identical. Which of the following is the correct ranking of the brightness of the bulbs? ANSWER: The brightness of 1 decreases permanently. B The brightness of 1 increases permanently. B The brightness of 1 decreases temporarily but gradually increases back to its original brightness. B The brightness of 1 does not change. B The brightness of 1 increases temporarily but gradually decreases back to its original brightness. B and have equal brightness, and is the dimmest. A B C All three bulbs have the same brightness. is brightest, is dimmest, and is in between. A C B and have equal brightness, and is the dimmest. B C A is the brightest, and and have equal brightness but less than . A B C A HW 08: Power and DC Circuits https://session.masteringphysics.com/myct/assignmentPrintView?assig... 22 of 25 17/10/22, 8:44 pm

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Correct Charged Capacitor and Resistor Learning Goal: To study the behavior of a circuit containing a resistor and a charged capacitor when the capacitor begins to discharge. A capacitor with capacitance is initially charged with charge . At time , a switch is thrown to close the circuit connecting the capacitor in series with a resistor of resistance . Part A What happens to the charge on the capacitor immediately after the switch is thrown? ANSWER: Correct Part B What is the current that flows through the resistor immediately after the switch is thrown? C q t = 0 R The electrons on the negative plate of the capacitor are held inside the capacitor by the positive charge on the other plate. Only the surface charge is held in the capacitor; the charge inside the metal plates flows through the resistor. The electrons on the negative plate immediately pass through the resistor and neutralize the charge on the positive plate. The electrons on the negative plate eventually pass through the resistor and neutralize the charge on the positive plate. I 0 HW 08: Power and DC Circuits https://session.masteringphysics.com/myct/assignmentPrintView?assig... 23 of 25 17/10/22, 8:44 pm

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Express your answer in terms of any or all of the quantities , , and . Hint 1. How to approach the problem Find the voltage across the resistor at . Then use Ohm's law to find the current through the resistor. Hint 2. Find the voltage at What is the voltage across the capacitor at time ? Express your answer in terms of any or all of the quantities , , and . ANSWER: ANSWER: Correct Note that since current is charge per time, the preceeding formula shows that the units of must be time. The combination of variables is called the time constant . It will occur frequently in problems involving a resistor and a capacitor. Problem 28.7 Part A What is the resistance of a 1600 (120 V) hair dryer? ANSWER: Correct Part B What is the current in the hair dryer when it is used? ANSWER: q R C t = 0 I 0 t = 0 V 0 t = 0 q R C = V 0 q C = I 0 q RC RC τ = RC W 9.00 Ω HW 08: Power and DC Circuits https://session.masteringphysics.com/myct/assignmentPrintView?assig... 24 of 25 17/10/22, 8:44 pm

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Correct Problem 28.12 Part A 1 is how many joules? Express your answer as an integer. ANSWER: Correct Optional Feedback Question Part A - Optional question: What concepts or problems, if any, were most difficult for you to understand? ANSWER: Score Summary: Your score on this assignment is 92.9%. You received 19.52 out of a possible total of 21 points. 13.3 A kWh 1 = 3600000 kWh J 3785 Character(s) remaining Essay answers are limited to about 500 words (3800 characters maximum, including spaces). (none provided) HW 08: Power and DC Circuits https://session.masteringphysics.com/myct/assignmentPrintView?assig... 25 of 25 17/10/22, 8:44 pm

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