Contradiction on kvl kcl laws question

Click For Summary
SUMMARY

The discussion centers on the application of Kirchhoff's Voltage Law (KVL) and the concept of "current shock" in a DC circuit involving capacitors and resistors. When the switch is closed at time t=0, the voltage at the junction of resistors R2 and R3 jumps to 6 volts, leading to a discontinuous current increase from 0 A to 1.5 A. This phenomenon creates a perceived contradiction in KVL due to the voltage drop across the capacitors, which must remain continuous despite the transient current changes. The continuity laws are upheld as the voltage across the capacitors remains constant during the transition.

PREREQUISITES
  • Understanding of Kirchhoff's Voltage Law (KVL)
  • Basic knowledge of DC circuits and capacitor behavior
  • Familiarity with resistors and their voltage drop characteristics
  • Concept of transient analysis in electrical circuits
NEXT STEPS
  • Study the behavior of capacitors in transient states in DC circuits
  • Learn about Kirchhoff's Current Law (KCL) and its applications
  • Explore the concept of voltage continuity across capacitors during switching events
  • Investigate the effects of circuit transients on current flow and voltage distribution
USEFUL FOR

Electrical engineering students, circuit designers, and anyone studying transient responses in DC circuits will benefit from this discussion.

nhrock3
Messages
403
Reaction score
0
http://i49.tinypic.com/1yu634.jpg

this is a part of the solution
"
the is a voltage drop on capacitor C1 which makes current shock on C1
and a current shock on R2 and R3
and it makes a KVL contradiction on the right branch and the outer branch.

and that's why the continuety laws holds"

what is current shock?
why its also on R2 and R3?
why KVL laws contradict?
why there is continuety ?
 
Physics news on Phys.org
Not sure what a current shock is or what contradiction they're referring to, but what they probably mean is this:

In a DC circuit, once any transients have died out, the capacitors are essentially open circuits, so no current is flowing anywhere in the circuit. If there's no current, there's no voltage drop across the resistors, so the 12-volt drop for each loop must occur across the capacitors.

At t=0, the switch is closed, causing the voltage of the point between R2 and R3 to discontinuously jump to 6 volts (relative to the bottom line of the circuit). For a capacitor, the current flowing through it may be discontinuous, but the voltage across it must be continuous. This means that t=0+, the capacitors still have a 12-volt drop across them; therefore, both resistors now have a 6-volt drop across them. The current therefore jumps discontinuously from 0 A to 1.5 A when the switch is closed.
 

Similar threads

Replies
2
Views
3K
  • · Replies 4 ·
Replies
4
Views
3K
  • · Replies 11 ·
Replies
11
Views
5K
  • · Replies 3 ·
Replies
3
Views
2K
  • · Replies 13 ·
Replies
13
Views
3K
  • · Replies 10 ·
Replies
10
Views
6K
  • · Replies 2 ·
Replies
2
Views
4K
  • · Replies 5 ·
Replies
5
Views
3K
  • · Replies 11 ·
Replies
11
Views
3K
  • · Replies 3 ·
Replies
3
Views
3K