PROBLEMS

  1. A positive charge of 8 x 10-10 C exerts a force on a negative charge of 8 x 10-10 C. The distance between the two charges is 10 cm. Find the magnitude of the attractive force that either charge exerts on the other.
  2. Determine the resistance of 10.0 m of copper wire that has a diameter of 2.6 mm and = 0.0172 x 10-6 -m.
  3. A battery charger puts 5 A into a 12-V auto battery. What is the power delivered into the battery?
  4. Calculate the power absorbed by the element in Figure P.1.
    Assume E = 200 mV and I = 5 V.




    Figure P.1 Circuit for Problem 4.
  5. Repeat Problem 4 assuming E = 200 mV and I = -5 A.
  6. If your skin has a resistance of 100,000 , and you touch a 9-V battery, what current will flow through you?
  7. What current will flow through you if you touch 120-V residential potential?
  8. How many minutes will it take a 2.00 kC to pass through an electrical conductor if the current is 3.00 A?
  9. What voltage is needed to run a vacuum cleaner drawing 12 A of current through a circuit with a resistance of 10 ?
  10. How much resistance is in a toaster that draws 6 A of current when plugged into a 120-V outlet socket?
  11. A car radio is designed to operate from a 6-V system uses 5 A of current as shown in Figure P.2. What resistance should be placed in series with this radio if it is to be used in a 12-V system.




    Figure P.2 Circuit for Problem 11
  12. Consider the RC circuit in Figure 12.2 . Assume R = 1000 ,
    C     = 10 µF, and E = 20 V. At the moment the battery is connected to the RC circuit, what is the value of the current? What is the RC time constant?
  13. Consider the RL circuit shown in Figure 13.2. If R = 100 , L is 1.0 H, and E = 10 V. Calculate the L/R time constant. Repeat the problem if L becomes 10.0 H.
               

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