Time constant for parallel RC circuit

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The time constant for a parallel RC circuit is determined by the formula τ = RC, where R is the total resistance in series with the capacitor. A participant initially suggested the time constant should be 1/2 RC due to a misunderstanding of the net resistance. Clarification was provided that the correct resistance affecting the time constant is the total resistance in series with the capacitor. The discussion also touched on the implications of using a non-ideal voltage source and how it could affect the circuit's behavior. Understanding the correct application of these principles is crucial for accurate calculations in circuit analysis.
Shivang kohlii
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Homework Statement



Question 6.
IMG-20190103-WA0005.jpeg


Homework Equations


Time constant = RC

The Attempt at a Solution


I think answer should be 1/2 RC as Rnet = 1/2R and to convert it to single resistance form we should first find Rnet
But the answer is coming out to be RC . How?

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upload_2019-1-3_9-49-47.png
 

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Shivang kohlii said:
But the answer is coming out to be RC . How?
What is the total resistance in series with the Capacitor? That is the resistance that shows up in the time constant (assuming the voltage source is ideal)...

Are you familiar with Differential Equations? That would be one way to show how this works in this circuit...
 
Bonus Question -- What if the voltage source is not ideal? How would that change things? :smile:
 

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