AC Circuit Analysis Ten years after graduating with a BSEE, you decide to go to graduate schools for a masters degree. In desperate need of income, you agree to sign on as a grader in the basic circuit analysis course. One of the problems asks the students to find v(t) in Figure P8–85 when the circuit operates in the sinusoidal steady state. One of the students offers the following solution:

vðtÞ ¼ ðR þ jvLÞ iðtÞ

¼ ð20 þ j20Þ 0:5 cos 200t

¼ 10 cos 200t þ j10 cos 200t

¼ 10 ffiffiffi2 p

cosð200t þ 45Þ

Is the answer correct? If not what grade would you give the student? If correct, what comments would you give the student about the method of solution?

Transcribed Image Text:

i(t) = 0.5 cos 200t A + v(t) 0.1 H 2012 FIGURE P8-85