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Capacitor not charging to supply voltage

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Hello Guys.
I am new to the world of electronics and I had done a simple circuit to verify the charging and discharging of a capacitor.

The circuit is as shown below:

1.png

 

My aim was to keep the lamp, L1 switched on for a further 5 seconds after the main switch has been opened. This is how I got the value 2.32F for the capacitor:

2.1.png

 

2.2.png

 

Hence I found that I needed a 2.32 F capacitor to have a discharge duration of 5 seconds.

 

My problems:
(1) The charging is taking way more than the calculated value ( > 63.661 seconds )

2.3.png

 

(2) The capacitor is not charging upto 12V. Tha maximum voltage attained is 7.098 V.

2.4.png

 

Please help me understand these variations from the calculated value :-(

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Solution
Accepted by topic author SatyamBhujan
11-23-2016 10:44 AM

Simple Ohm's Law.  The final value of the capacitor voltage in a DC circuit will be the voltage at that point as if the capacitor had been removed.  Resistor R2 and lamp L1 create voltage divider so 7 V appears to be correct.

 

Lynn

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Thank you Sir.. You were right..
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