Charge on the capacitor after changing the switch position

[Fatima Hasan]

Homework Statement

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)
V_c = 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 ?

 

[cnh1995]

Vc = 0 , because the switch is connected for a long time.

Are you sure?

Is my answer correct ?

No, t=2s doesn't appear anywhere in your equations.

 

[Fatima Hasan]

Are you sure?

No, t=2s doesn't appear anywhere in your equations.

 

[cnh1995]

View attachment 226355

Looks good.