1 / 31

Understanding Series and Parallel Circuits in Electric Circuits

Explore the principles of series and parallel circuits in EE fundamentals with examples of resistors configurations. Learn about Kirchhoff laws, voltage sources, and current division rules. Discover how to calculate resistance, voltage drops, power dissipation, and more.

apence
Download Presentation

Understanding Series and Parallel Circuits in Electric Circuits

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Series Circuits EE 2010: Fundamentals of Electric Circuits Mujahed AlDhaifallah

  2. Is this a series circuit? R1 R2

  3. Is this a series circuit? R1 R3 R2

  4. Is this a series circuit? R1 R3 R2

  5. Series Circuit • Two elements are in series if • They have only one terminal in common. • The common point in the two elements is not connected to a third current carrying element.

  6. Resistance • Resistance is proportional to length length direction of current flow

  7. Resistance • R = ρL/A • ρ is the resistivity of the material (units?)

  8. length length direction of current flow direction of current flow Resistance • What happens if two elements are connected back to back?

  9. Resistance • R = ρ (L1+L2)/A • R = R1 + R2 • The total resistance of a series circuit is the sum of all the resistances in the path

  10. R1 R2 Resistance • The resistance seen by the source • R=R1+R2 • The two circuits on the right are equivalent R1+R2

  11. Voltage Drop? • The current through each resistor is calculated by the Ohm’s law • =V1/R1 • Where V1 is the voltage across the resistor. • =V/RT • Where RT is the total resistance in the circuit. • V1 = VxR1/RT

  12. Power? • Power dissipated in each resistor • P1 = V12/R1 • P1 = (V2/RT2)x R1 • Total power = V2/RT = P1 + P2 + …

  13. Voltage Sources in Series • Voltage sources can be connected in series to increase or decrease the total voltage applied to the system. • Net voltage is determined by summing the sources having the same polarity and subtracting the total of the sources having the opposite polarity.

  14. Kirchhoff’s Voltage Law • The algebraic sum of the potential rises and drops around a closed loop is zero.

  15. R1 R2 KVL • V + V1+V2 = 0 • Can anyone prove this mathematically? V1 V V2

  16. Voltage Divider Rule • In a series circuit the voltage across the resistive elements will divide as the magnitude of the resistors

  17. Interchanging Series Elements • Elements of a series circuit can be interchanged without affecting the total resistance, current, or power to each element. • In the Figures below, resistors 2 and 3 are interchanged without affecting the total resistance

  18. This is not a loop. Or is it? Ground Terminal

  19. This is not a loop. Or is it? Ground terminal means that the two points are both connected to ground and are at a zero potential. So this is a loop. Ground Terminal

  20. Internal Resistances • The ideal voltage source has no internal resistance and an output voltage of V volts with no load or full load • Every practical voltage source (generator, battery, or laboratory supply) has some internal resistance. • Voltage across the internal resistance lowers the source output voltage when a load is connected. • For any chosen interval of voltage or current, the magnitude of the internal resistance is given by Rint = VL / IL

  21. Parallel Circuits EE 2010: Fundamentals of Electric Circuits Mujahed AlDhaifallah

  22. Are these resistors in Parallel?

  23. Are these resistors in Parallel?

  24. Are these resistors in Parallel?

  25. Parallel Elements • Two Elements, branches or networks are in parallel if they have two points in common.

  26. Resistance • Resistance is inversely proportional to the cross sectional area direction of current flow

  27. direction of current flow direction of current flow Resistance • Resistance is inversely proportional to the cross sectional area

  28. Resistance • R = ρL/(A1+A2) • Solving in terms of R1 and R2 gives • 1/R = 1/R1 + 1/R2 • The total value of the resistance is always smaller than the smallest resistance

  29. Resistance, etc. • The total resistance will decrease with each new added parallel branch • The voltage across each resistor is the same • The total current is the sum of all the branches • The total power dissipated is the sum of power dissipated in all resistors.

  30. Kirchhoff’s Current Law • KCL states that the algebraic sum of the currents entering and leaving a point or junction is zero. • i1+i2+i3+i4=0 i1 i2 i3 i4

  31. Current Divider Rule • For parallel elements of different value the current will split with a ratio equal to the inverse of their resistor value

More Related