The plates of a capacitor are charged to a potential difference of 320 volts and are then connected across a resistor. The potential difference across the capacitor decays exponentially with time. After 1 second the potential difference between the plates of the capacitor is 240 volts, then after 2 and 3 seconds the potential difference between the plates will be [MP PET 1996]

• A.            200 and 180 V
• B.                                      180 and 135 V
• C.            160 and 80 V                         
• D.            140 and 20 V