Need help in step response circuit diagram

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The discussion revolves around understanding the transformation of a circuit diagram to the s-domain after a switch changes position. The user is confused about why a 10V source is included as 10/s in the s-domain transformation when the switch has already moved to position b. Clarification is sought on whether the answer key is incorrect or if there is a misunderstanding of the concepts. It is established that since the switch was at position 'a' for a long time, the voltage across the capacitor at t=0+ is indeed 10V. The conversation concludes with agreement on the voltage value.
whatphysics
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This isn't a homework question! I posted the question for context purpose.

So I understand that at t>0 the switch moves to b. Hence the first circuit diagram (pictured) I understand.

However for the 2nd circuit diagram (picture 2) when asked to transform to s domain. Why does this answer include the 10/s. To my understanding because the switch already switched to b, the 10V is no longer considered hence shouldn't be included as 10/s in the transformation circuit.

Can anyone explain this to me? Whether the answer key is wrong or are my concepts wrong?

Thank you so much in advance!
 

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The switch was at 'a' for a long time. So what is the voltage across the capacitor at t=0+?
 
As I can see from picture 1, it asks for the voltage V(t) for ##t\geq 0## so we are interested for the V(t) for t=0 too (not only for t>0).
 
Delta² said:
As I can see from picture 1, it asks for the voltage V(t) for ##t\geq 0## so we are interested for the V(t) for t=0 too (not only for t>0).
Ah that would make sense..thanks!
 
cnh1995 said:
The switch was at 'a' for a long time. So what is the voltage across the capacitor at t=0+?
Um 10V?
 
whatphysics said:
Um 10V?
Yes.
 
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