| Electrical Engineering is a free introductory textbook to the basics of electrical engineering. See the editorial for more information.... |
|
Home  Circuits With Resistance, Inductance, and Capacitance Series Circuits With Resistance and Capacitance |
|||||
 Search the VIAS Library | Index
|
  |
||||
|
Series Circuits With Resistance and CapacitanceAuthor: E.E. Kimberly In the circuit of Fig. 5-15 the same current flows in both the resistance and the reactance. The resistance voltage drop is in phase with the current, and the capacitive reactance voltage drop lags the current by 90°, as indicated in Fig. 5-16. The angle 0 is the characteristic angle.
Example 5-7. - A resistor with R = 30 ohms is connected in series with a .condenser with C = 50 microfarads to a 220-volt line whose frequency is 60 cycles. How much current will flow?
Solution. - The capacitive reactance is
The current is found as follows:
Example 5-8. - A resistor whose resistance is 10 ohms has a maximum safe current capacity of 5 amperes. It is to be used on a 220-volt, 60-cycle line in series with a condenser. What must be the capacitance of the condenser to limit the current to a safe value?
Solution. - The impedance is But Therefore,
from which C = 0.000061 farad or 61 microfarads
|
|||||
| Home Circuits With Resistance, Inductance, and Capacitance Series Circuits With Resistance and Capacitance |
|
||||
