Two identical capacitors each of capacitance `5 muF` are charged to potentials 2 kV and 1 kV respectively.The -ve ends are connected together. When the +ve ends are also connected together, the loss of energy of the system is

Options

A. 160 J
B. 0 J
C. 5 J
D. `1.25` J

Answer

D

Explanation

Loss of energy ` = (1)/(2) (C_(1)C_(2))/((C_(1) + C_(2)))(V_(1)-V_(2))^(2)`
` = (1/2)(5 xx 5 xx 10^(-12))/((5 + 5)xx 10^(-6))(2000-1000)^(2)`
` = (5xx5xx1)/(2xx10) = (5)/(4) = 1.25 `J.