Question

Find the energy stored in the 5 mC capacitor

14. Find the energy stored in the 5 uF capacitor. aix10 (b) 6.0x104 (c) 5.2x104 J (d) 22x10.1 5uF 15uF 10uF 15uF 20 V

Answer 1

I have solved the question but I think given options are incorrect . The correct answer which I am getting is 1.11e-4 J. Please have a look at my solution

First, find equivalent capacitance, 4 mu F and 6 mu F are in parallel Therefore c_1 = 4 + 6 = 10 mu F This is in series with 10 mu F Therefore c_2 = 1/1/ + 1/10 = 5 mu F Now, 5 mu F, 10 mu F, 15 mu F are in parallel so, c_3 = 30 mu F c_4 = 1/1/3 + 1/15 = 10 mu F Therefore we have rightarrow \r\n Therefore c_Total = 5 + 1 = 15 mu F Therefore Q_Total = c_Total times v = 15 times 20 = 300 mu c Therefore Q (across 10 mu F combination) = 10 times 20 degree = 200 mu c Q (across 15 mu F) = Q (across combination of 5 mu F, 10 mu F, 15 mu F) Therefore v = Q/c = 200/30 = 6.667 v Therefore Q (5 mu F) = cv = 5 times 6.667 = 33.33 mu c Therefore Energy = Q^2/2c