Question #18ca7

1 Answer
May 4, 2017

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Same potential across each in parallel so:

#Q = CV implies Q_1/5 = Q_2/7 = implies Q_1 = 5/7 Q_2 #

In addition we have conservation of charge.

Total charge before they are joined, #Q_i # was:

#sum Qi = (5 * 450 + 7 * 750)/(10^(6)) =3/400 C#

#Q_i = Q_1 + Q_2#

#implies Q_2 = 7/1600 C, Q_1 = 1/320 C#

Voltage:

#V = Q_2/C_2 = (7/1600)/(7 * 10^(-6)) = 625 V#