A `10 muF` capacitor and a `20 muF` capacitor are connected in series across a `200 V` supply line. The chraged capacitors are then disconnected from the line and reconnected with their positive plates together and negative plates together and no external voltage is applied. what is the potential difference across each capacitor ?

Options

A. `(400)/(9)" V"`
B. `(800)/(3)" V"`
C. `400" V"`
D. `200" V"`

Answer

A

Explanation

Equivalent capacitance of series combination
`C_(s)=(10xx20)/(10+20)=(200)/(30)=(20)/(3)muF`
As `" "Q=C_(s)V`
or, `" "Q=(20)/(3)muFxx200V`
or, `" "Q=(4000)/(3)muC`
Now, `" "V=(400muC)/(3xx30muF)`
`=(4000)/(90)V=(400)/(9)V`