18.若電壓及電流瞬間值方程式為
【木木琮詠】評論
V(t)=156sin(377t+30°)V、i(t)=14.1sin(377t-15°)i
【長貓】評論
Θ=Θv -Θi =30-(-15) =45o (電壓超前)