5:04 1. [-/1 Points] Assignment Submission For this assignment, you submit answers by question parts. The number of submissions remaining for each question part only changes if you submit or change the answer. Assignment Scoring Your last submission is used for your score. MY NOTES ASK YOUR TEACHER Prelecture Exploration: Electrical Power DETAILS SERPSE10 26.PLE.001. This question has several parts that must be completed sequentially. If you skip a part of the question, you will not receive any points for the skipped part, and you will not be able to come back to the skipped part. Lalasa has always been interested in electricity and electrical power and is excited to be learning about the subject in physics class. She and her friend Mackenzie are study partners, and they decide to spend some time exploring electrical power. Lalasa reminds Mackenzie that electrical power is the rate at which energy is converted from the electrical energy of the moving charges to some other form, for example, heat, mechanical energy, or energy stored in electric fields or magnetic fields. Lalasa and Mackenzie use this simulation to gain a deeper understanding of electrical power. They can click the switch to open or close the circuit and use the sliders to adjust the resistance and the voltage. The current and power are shown in the counter boxes at the bottom. They should be careful: The resistor is designed to dissipate only 20 W of power! 2. [-/1 Points] Submit Answer MY NOTES voltage 回 6 ***** 20 Need Help? Read It Need Help? b Submit Skip (you cannot come back) webassign.net a AV PRACTICE ANOTHER Click here to open the simulation in a new window. ASK YOUR TEACHER I= 0.00 Read It S (off) A DETAILS SERPSE10 26.1.P.007. Watch It Power = (b) What is the value of the current density? kA/m² Part 1 of 9 - Current Lalasa asks Mackenzie if she knows what current is. Which of her responses is correct? O "The work that would have to be done, per unit charge, against a static electric field to move a charge between two points." O "An object's opposition to the flow of charge carriers." O "The flow of electric charges through a piece of material." O "A device that converts stored chemical energy into useful electrical energy." PRACTICE ANOTHER R 0.00 W d (a) What is the instantaneous current through the surface at t = 1.10 s? A resistance 30 984 ΙΩ [****** The quantity of charge q (in coulombs) that has passed through a surface of area 2.10 cm² varies with time according to the equation q = 5t³ + 8t + 6, where t is in seconds. 10 100 5:05 Need Help? Submit Answer 2. [-/1 Points] MY NOTES Need Help? Submit Answer 3. [-/1 Points] MY NOTES The quantity of charge q (in coulombs) that has passed through a surface of area 2.10 cm² varies with time according to the equation q = 5t³ + 8t + 6, where t is in seconds. (a) What is the instantaneous current through the surface at t = 1.10 s? ASK YOUR TEACHER (b) What is the value of the current density? kA/m² Need Help? 4. [-/1 Points] MY NOTES Submit Answer Read It DETAILS SERPSE10 26.1.P.007. 5. [-/1 Points] MY NOTES Need Help? Read It ASK YOUR TEACHER Submit Answer DETAILS An electric current in a conductor varies with time according to the expression I(t) = 116 sin (90xt), where I is in amperes and t is in seconds. What is the total charge passing a given point in the conductor from t = 0 to t = 1/180 s? C Read It DETAILS ASK YOUR TEACHER Read It DETAILS (a) A lightbulb has a resistance of 250 2 when operating with a potential difference of 145 V across it. What is the current in the lightbulb (in mA)? mA (b) What If? What would be the current in the lightbulb (in mA) if it were used in Barbados, where the potential difference across it would be 115 V? mA Material Silver Copper Gold ASK YOUR TEACHER Aluminum Tungsten Iron Watch It Platinum Lead Nichrome SERPSE10 26.1.P.009. Carbon Watch It (a) A 34.1-m length of copper wire at 20.0°C has a radius of 0.29 mm. If a potential difference of 8.00 V is applied across the length of the wire, determine the current in the wire. (Use the values in the following table.) Resistivity (2. m) Temperature Coefficient of Resistivityb a [(°C)-¹] Germanium PRACTICE ANOTHER Silicond Glass SERPSE10 26.2.OP.005. PRACTICE ANOTHER Watch It webassign.net PRACTICE ANOTHER SERPSE10 26.4.OP.015.MI. PRACTICE ANOTHER 1.59 x 10-8 1.7 x 10-8 2.44 x 10-8 2.82 x 10-8 5.6 x 10-8 10.0 x 10-8 11 x 10-8 22 x 10-8 1.00 x 10-6 3.5 x 10-5 0.46 2.3 x 10³ 3.8 x 10-3 3.9 x 10-3 3.4 x 10-3 3.9 x 10-3 4.5 x 10-3 5.0 x 10-3 984 3.92 x 10-3 3.9 x 10-3 0.4 x 10-3 -0.5 x 10-3 -48 x 10-3 -75 x 10-3 5:05 5. [-/1 Points] MY NOTES ASK YOUR TEACHER MY NOTES (a) A 34.1-m length of copper wire at 20.0°C has a radius of 0.29 mm. If a potential difference of 8.00 V is applied across the length of the wire, determine the current in the wire. (Use the values in the following table.) Resistivity (m) Temperature Coefficient of Resistivity a [(°C)-¹] 6. [-/1 Points] DETAILS SERPSE10 26.4.OP.015.MI. Material Silver Submit Answer MY NOTES Copper Gold Aluminum Tungsten Iron Platinum Lead Nichrome Germanium Carbon Submit Answer Silicon Hard rubber Glass Quartz (fused) Sulfur Read It DETAILS 1.59 x 10-8 1.7 x 10-8 W PRACTICE ANOTHER 2.44 x 10-8 2.82 x 10-8 5.6 x 10-8 Need Help? Read It 10.0 x 10-8 11 x 10-8 7. [-/1 Points] DETAILS 22 x 10-8 1.00 x 10-6 3.5 x 10-5 webassign.net 2.3 x 103 1010 1014 0.46 ASK YOUR TEACHER 75 x 1016 =1013 1015 Master It SERPSE10 26.6.P.028. (a) All values at 20°C. All elements in this table are assumed to be free of impurities. (b) See the section "Resistance and Temperature". (c) A nickel-chromium alloy commonly used in heating elements. The resistivity of Nichrome varies with composition and ranges between 1.00 x 10-6 and 1.50 x 10-60 m. (b) If the wire is heated to 38.0°C while the 8.00-V potential difference is maintained, what is the resulting current in the wire? A Need Help? (d) The resistivity of silicon is very sensitive to purity. The value can be changed by several orders of magnitude when it is doped with other atoms. (b) Repeat the calculation for a 12-gauge aluminum wire. W This answer has not been graded yet. PRACTICE ANOTHER Watch It ASK YOUR TEACHER 3.8 x 10-3 3.9 x 10-3 3.4 x 10-3 3.9 x 10-3 SERPSE10 26.A.OP.027.MI. 4.5 x 10-3 5.0 x 10-3 Residential building codes typically require the use of 12-gauge copper wire (diameter 0.205 cm) for wiring receptacles. Such circuits carry currents as large as 20.0 A. If a wire of smaller diameter (with a higher gauge number) carried that much current, the wire could rise to a high temperature and cause a fire. (Table of resistivities) PRACTICE ANOTHER 3.92 x 10-3 3.9 x 10-3 (a) Calculate the rate at which internal energy is produced in 2.35 m of 12-gauge copper wire carrying a current of 20.0 A. 0.4 x 10-3 -0.5 x 10-3 Explain whether a 12-gauge aluminum wire would be as safe as a copper wire. -48 x 10-3 -75 x 10-3 984 5:05 Done webassign.net AA Circuits Carry currents as large as 20.0 A. Il a wire or smaller arameter (with a higher gauge number) Carned that much current, the wire could rise to a high temperature and cause a fire. (Table of resistivities) MY NOTES (a) Calculate the rate at which internal energy is produced in 2.35 m of 12-gauge copper wire carrying a current of 20.0 A. (b) Repeat the calculation for a 12-gauge aluminum wire. W Need Help? Read It Submit Answer 7. [-/1 Points] Explain whether a 12-gauge aluminum wire would be as safe as a copper wire. MY NOTES 8. [-/1 Points] This answer has not been graded yet. Submit Answer MY NOTES W 9. [-/1 Points] A particular wire has a resistivity of 2.5 x 10-8 2 m and a cross-sectional area of 2.5 x 10-6 m². A length of this wire is to be used as a resistor that will receive 47 W of power when connected across a 20-V battery. What length of wire is required? km Need Help? Need Help? ASK YOUR TEACHER Submit Answer DETAILS Read It DETAILS ASK YOUR TEACHER Need Help? Watch It Submit Answer SERPSE10 26.A.OP.027.MI. One wire in a high-voltage transmission line carries 1 000 A starting at 670 kV for a distance of 230 mi. If the resistance in the wire is 0.500 /mi, what is the power loss due to the resistance of the wire? MW Read It DETAILS Master It SERPSE10 26.A.P.035. ASK YOUR TEACHER Read It PRACTICE ANOTHER Watch It PRACTICE ANOTHER SERPSE10 26.A.OP.033. An electric utility company supplies a customer's house from the main power lines (120 V) with two copper wires, each of which is 46.0 m long and has a resistance of 0.104 2 per 300 m. (a) Find the potential difference at the customer's house for a load current of 114 A. (b) For this load current, find the power delivered to the customer. kW (c) Find the rate at which internal energy is produced in the copper wires. W PRACTICE ANOTHER Watch It 984 Home My Assignments Request Extension ₁ 6. [-/1 Points] MY NOTES DETAILS SERPSE10 26.6.P.028. ASK YOUR TEACHER Residential building codes typically require the use of 12-gauge copper wire (diameter 0.205 cm) for wiring receptacles. Such circuits carry currents as large as 20.0 A. If a wire of smaller diameter (with a higher gauge number) carried that much current, the wire could rise to a high temperature and cause a fire. (Table of resistivities) (a) Calculate the rate at which internal energy is produced in 2.35 m of 12-gauge copper wire carrying a current of 20.0 A. W (b) Repeat the calculation for a 12-gauge aluminum wire. W PRACTICE ANOTHER Explain whether a 12-gauge aluminum wire would be as safe as a copper wire. This answer has not been graded yet. Submit Answer Need Help? Read It Watch It