a) linear frequency is 275 Hz; angular frequency is 1730 rad/sec.
b) Current maximum is 365 mA.
a) q = Q/sqrt(3)
b) t = 0.152 T
a) fmax / fmin = 6.0
b) C = 36 pF in parallel; L = 0.22 mH.
(Note: if you get 8.6 mH you have forgotten to convert linear frequency to angular frequency!)
a) Utot = 1.98 microJ
b) qmax = 5.56 microC
c) imax = 12.6 mA
d) phase angle is -46.9 degrees
Why negative? We found that the cosine of the phase angle should be 0.68; thus the phase angle may be +/- 46.9 degrees. The sign is chosen depending on whether the capacitor is charging or discharging. To decide, look at the time derivative of the charge at t=0, which is proportional to the negative of the sine of the phase angle. For a charging capacitor, this derivative should be positive; thus the choice of -46.9 degrees.
e) phase angle is +46.9 degrees