Answer the following Problems: 1. An 800 mA current is passing through a resistor. The voltage applied to the resistor is 5.0 V. What is the value of the resistance of the resistor? 2. A resistor has a resistance of 3.20 k2. A voltage of 12.0 V is applied across the resistor. What is the value of the current through the resistor? 3. The resistance of a household water heater is 25.0 Ohms. If the current passing through the heater is 4.40 A, what is the voltage applied? 4. In one home audio system, the wires connecting a speaker to the stereo is 20.0 m long. To keep the losses low, we need to ensure that the resistance is no more than 0.10 Ohms per wire. If we use copper wire, a) What cross-sectional area should the copper wire have? b) What is the radius of the copper wire?

Answer the following Problems: 1. An 800 mA current is passing through a resistor. The voltage applied to the resistor is 5.0 V. What is the value of the resistance of the resistor? 2. A resistor has a resistance of 3.20 k2. A voltage of 12.0 V is applied across the resistor. What is the value of the current through the resistor? 3. The resistance of a household water heater is 25.0 Ohms. If the current passing through the heater is 4.40 A, what is the voltage applied? 4. In one home audio system, the wires connecting a speaker to the stereo is 20.0 m long. To keep the losses low, we need to ensure that the resistance is no more than 0.10 Ohms per wire. If we use copper wire, a) What cross-sectional area should the copper wire have? b) What is the radius of the copper wire?

University Physics Volume 2

18th Edition

ISBN:9781938168161

Author:OpenStax

Publisher:OpenStax

Chapter10: Direct-current Circuits

Section: Chapter Questions

Problem 45P: A child's electronic toy is supplied by three 1.58-V alkaline cells having internal resistances of...

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