For the circuit shown in the figure below, C = 6.02 µF, script e = 90 V, and R =
ID: 1323833 • Letter: F
Question
For the circuit shown in the figure below, C = 6.02 µF, script e = 90 V, and R = 370 . After having been at contact a for a long time, the switch throw is rotated to contact b. answer all please
For the circuit shown in the figure below, C = 6.02 muF, E = 90 V, and R = 370 ohm. After having been at contact a for a long time, the switch throw is rotated to contact b. 1) What is the charge on the upper plate of the capacitor just as the switch throw is moved to contact b? 2) What is the current just after the switch throw is rotated to contact b? 3) What is the time constant of this circuit? 4) How much charge is on the upper plate of the capacitor 7 ms after the switch throw is rotated to contact b?Explanation / Answer
a)
Charge
Qo=C*E =(6.02*10-6)*90
Qo= 541.8 uC
b)
Current
Io=E/R =90/370
Io=0.2432 A
c)
Time Constant
T=RC =(6.02*10-6)*370
T=2.23 ms
d)
In a RC circuit charge as a function of time is given by
Q(t)=Qoe-t/T
at t=7 ms
Q(7ms) =(541.8)e-7/2.23
Q(7ms)=23.4 uC