# Find time constant

1. The problem statement, all variables and given/known data
The time constant of charging for the capacitor shown in the figure is

2. Relevant equations

See attached diagram

3. The attempt at a solution

$\tau = R_{eq} C$

$R_{eq} = R/2$

So the answer should be t= RC/2. But the correct answer is 0! :confused:

Attached Images
 20140422_214153.jpg (43.6 KB)

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