In the circuit shown, R1 = 10 Ω, R2 = 4 Ω, R3 = 10 Ω, ε = 10 V, and capacitor has a capacitance C = 2 μF. Determine the energy stored in the capacitor when switch S has been closed for a long time.
http://tinypic.com/r/24v678w/5

Question

In the circuit shown, R1 = 10 Ω, R2 = 4 Ω, R3 = 10 Ω, ε = 10 V, and capacitor has a capacitance C = 2 μF. Determine the energy stored in the capacitor when switch S has been closed for a long time.
http://tinypic.com/r/24v678w/5

anonymous · Answer

After a long time, the voltage in the capacitor is determined by the combination of resistors: Vc=Vbattery x (R2||R3)/(R1+R2||R3), where R2||R3 is the parallel of R2 and R3 With this value of Vc, you can calculate the Energy like E=1/2 x C x Vc^2