Hey all, i dont know if you can help me. I do Know all the background information on ac circuits, and the calculations on complex numbers in ac circuits etc, but i am struggling with this question on a past paper, in my revision for my exam. Any help is much apreciated, even if it just points me in the right direction.

(a) Consider the a.c. current i(t) = 12sin(2π50t+90º) mA. Give the peak value (amplitude), angular frequency, frequency, period and phase angle using the correct units.

Many Thanks

 

i(t)=A*sin(wt+phi)
Where A is amplitude, w=angular frequency, w=2πf (f=frequency), period =1/f and phi=phase angle. Now you can figure out the required.