Question

Two capacitors of capacitance 2.0uF and 4.0uF respectively, are each given a charge of 120uC. The positive plates are now connected together, so too are the negative plates. Calculate the new potential difference between the plates of the capacitors. Calculation shows that the total energy stored by the capacitors has decreased. Explain this change in energy.

Answer 1

Answer

Potential difference is given

$V=\frac{Q}{C}=\frac{12\times10^{-6}}{6\times10^{-6}}=2$ volts

Firstly energy of capacitors are given individual so it's less.

After plates connects potential difference increases which makes increment in energy of capacitors.