Current in an RC circuit

Question

A circuit comprises a 9 V battery which is connected in series to two 1 MΩ resistors
that are in a parallel combination. The circuit is then completed by an open switch
and two 50 nF capacitors that are also connected in parallel.

 

The switch is closed at time t = 0 s. Find the current flowing through the circuit
after a time of 200 m s???

 

I simplified this circuit so you have a 9V battery in series with a 100 nF  and a 0.5  MΩ

 

This gives the time constant to be 0.05.

 

So when the switch is closed the capacitor is charging.

 

I used the equation 

 

                          i = - V_o/R ( e^-t/RC  )

 

V_o =9V     R= 0.5  MΩ   t= 0.2 s    

 

Plugging in the values I get - 3.29 x10^-7 A

 

However the answer we have been provided is 1.65x10^-7A which is half my value. Is the answer I have been provided wrong and I am correct?

Answer 1

Yup. I get the same answer as you. Looks to me like the answer provided is in error.

Why do you have the current as negative ??

It should be positive.