Charge on the capacitor after changing the switch position

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Homework Help Overview

The discussion revolves around a problem involving a capacitor's charge after changing the position of a switch in an electrical circuit. The subject area includes concepts from circuit analysis and capacitor behavior.

Discussion Character

  • Exploratory, Assumption checking

Approaches and Questions Raised

  • Participants discuss the application of Kirchhoff's Voltage Law (KVL) and the behavior of voltage across the capacitor when the switch is in different positions. Questions arise regarding the initial conditions and the implications of time in the equations presented.

Discussion Status

Some participants express uncertainty about the correctness of the original poster's calculations and assumptions, particularly regarding the voltage across the capacitor and the relevance of time in the analysis. Others provide feedback that suggests the initial approach is acceptable, but questions remain about specific details.

Contextual Notes

There is mention of a time variable (t=2s) that does not appear in the original equations, indicating a potential gap in the information provided or assumptions made in the problem setup.

Fatima Hasan
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Homework Statement


73_FFCE1_F-7820-4_D4_A-_BE3_F-_CAB58_E0_EED31.jpg


Homework Equations


V = I R
Q= CV

The Attempt at a Solution


When the switch is connected to position a :
20-106 * I = 0 ( KVL)
Vc = 0 , because the switch is connected for a long time.
I = 2*10-5 A
When the switch is connected to position b :
Q/(4*10-6) - 106 *2*10-5 = 0 (KVL)
Q =8*10-5 = 80μC
Is my answer correct ?
 

Attachments

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Fatima Hasan said:
Vc = 0 , because the switch is connected for a long time.
Are you sure?
Fatima Hasan said:
Is my answer correct ?
No, t=2s doesn't appear anywhere in your equations.
 
cnh1995 said:
Are you sure?

No, t=2s doesn't appear anywhere in your equations.
4%7D%20%3D%2048.png
 

Attachments

  • 4%7D%20%3D%2048.png
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