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I was experimenting with capacitor voltage divider circuits but something unusual happened. Circuit is really simple , I connected 100uF 16v capacitor into 13.85V 50hz AC supply Xc is 26.5 ohm So I expected current will be 0.5A but multimeter showed 1A-1.2A then capacitor exploded.

I assumed capacitor overheated and that caused the explosion but why current is twice than it supposed to be ?

I made similar circuits with 47uF and 1uF capacitors and everything was right , why 100uF acts differently ?

Capacitors are radial electrolytic

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    \$\begingroup\$ How did you connect it? If you had some inductance in the connection, it would reduce the total reactance and increase the current delivered. \$\endgroup\$ – The Photon Sep 2 at 1:57
  • \$\begingroup\$ Only one capacitor nothing else .capacitor's positive side connected to supply other side connected to multimeter's positive probe and multimeter's negative probe connected to supply \$\endgroup\$ – Mordecai Sep 2 at 1:58
  • \$\begingroup\$ What was the supply? a transformer connected to mains? \$\endgroup\$ – The Photon Sep 2 at 2:03
  • \$\begingroup\$ Yeah I just thought same thing too , I didn't realize supply is step down transformer so it have inductance too . Thanks \$\endgroup\$ – Mordecai Sep 2 at 2:05
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    \$\begingroup\$ @Mordecai No, it isn't the peak-to-peak voltage that is causing your problem. The capacitor only sees half that, the peak, on each half cycle because the other end can be thought of as being connected to the middle (0V) of the signal. However 13.85V RMS has a peak voltage of 19.6V which exceeds the 16V rating. In any case, as several people have pointed out, an electrolytic capacitor is not designed to be reverse biassed and I guess that you were just lucky that the other capacitors you tried didn't also explode. \$\endgroup\$ – Peter Jennings Sep 2 at 11:11

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