What Happens to Current Direction in an RL Circuit When the Switch is Opened?

AI Thread Summary
When the switch in an RL circuit is opened after being closed for a long time, the current direction in the right-hand loop containing the inductor and resistors R2 and R3 becomes counterclockwise. Initially, while the switch is closed, the current flows clockwise through the circuit. Upon opening the switch, the inductor maintains the current flow due to its stored energy, causing a change in direction. The discussion highlights confusion about the behavior of current immediately after the switch is opened, emphasizing the importance of understanding inductor behavior in circuits. The correct answer to the current direction question is counterclockwise.
syhpui2
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Homework Statement



A circuit made with a battery, a switch, an inductor. and three resistors is shown in the figure. To begin with, switch S has been open for a long time. Then at time t = 0 the switch is closed.

http://i.imgur.com/ws5UD.png
ws5UD.png


After being closed for a long time, the switch S is now opened.
What is the direction of the current in the right hand loop containing L, R2 and R3 immediately after the switch is opened?

(a) clockwise
(b) counterclockwise Correct Answer

Homework Equations



Ampere's law?

The Attempt at a Solution



I am not sure how do I ind the direction of current if switch is opened? Should be no current?

Thx
 
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Before the switch is opened, what currents are flowing and in what directions?
 
gneill said:
Before the switch is opened, what currents are flowing and in what directions?

There are current on r2,r3 and inductor and it is clockwise...
 
syhpui2 said:
There are current on r2,r3 and inductor and it is clockwise...

No, that's not right. Yes, there is current through the inductor, but what is that current and what is the voltage across the inductor? What about R1?
 

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