QUIZ 22 CH.22
 
SELECTED DISCUSSIONS TO exercises/problems BELOW.
YOU ARE RESPONSIBLE FOR ALL  PROBLEMS EVEN THE ONES WITHOUT DISCUSSIONS, WHICH ARE DESIGNED TO HELP YOU DO RELATED EXERCISES. Each sublist is separated by a semi-colon ";" and ends with the name of the section for those exercises. WE WILL REVIEW THEM IN-CLASS THE LAST WEEK BEFORE FINAL EXAM. 
CH.  22:  SEE LECTURE NOTES
CH. 22  MULTIPLE CHOICE TBA  - Exercise/problems  1, 3, 5, 11, 12, 13, 19 
TURN IN: 1, 3, 5, 11, 12, 19 
* DISCUSSIONS PROVIDED. 
1. SEE LECTURE NOTES: In a resistor, the current I and  voltage VR are in phase: Im = VRm/R, where voltage across R is VR = VRm*cos wt and I = VR/R. Irms = Im/(1.41..), where 1.41... = square root of 2. Note also that Irms = 0.707*Im
3. (a) wL = 1/(wC)  Solve for w. (b) Plug in numbers; evaluate  wL  or  1/(wC) numerically since they are equal.
5. Im = VLm/(wL), where VLm = 12.0 (V).
11. Use equation 22.18. Vrms2   =  VRrms2  + (VLrms   -   VCrms)2   , where Vrms is the rms value of voltage source. The other rms voltages are given.  Evaluate and take the positive square root to get the rms voltage source value.
12. Use the formula for impedance Z on page 745, equation 22.22, and  set C = infinity, effectively removing C from the formula. 

Z2 = R2 + w2L2.   Set w = 2*pi*120 rad/s, where pi = 3.14...and solve for Z. With this value of Z,  set (2Z) = R2 + w' 2L2 , where w ' is the new frequency doubling the impedance.

13. Use Z2   =  R2  + (wL  -   1/wC)2 .
(a) Plug in the 3 values of w given and evaluate Z in each case.
(b) Im = Vm/Z, where Z is the total impedance for the RLC series circuit and  Vm and Im are the voltage  source and current amplitudes. Plug in the 3 values of w given and evaluate Im  in each case to answer the question.
(c) Use equation 22.23.
(d) Draw a diagram of the phasors (vectors) like that on page 7 of  LECTURE NOTES. The lengths of each voltage vector (phasor) can be easily scaled in your diagram  since they  are given by VRm = Im*R , VLm = Im*(wL), and
VCm = Im*(1/wC) =(1/ wC)*Im .
19. See section 22.5 and page 8 of LECTURE NOTES .