Question

Home Students Library Help Portfolio matics (TU Open Learning) SPT-13828-0721-SST-2019 - "Real" Assessments Topic 2 Trigonometric Methods V3.3 nmetic m BAS The instantaneous value of current i (amps) att seconds in a circuit is given by i = 30 sin(250xt+0.7) Find the value of Memory 3 marks a) Answered The amplitude 30 8 marks Partially answered Submit part 4 + 7 + 6 marks Unanswered 1 mark Answered 8 marks Unanswered 6 marks The period in ms Round your answer to 2 decimal places Submit part m 1 mark Unanswered The frequency Submit part art a search Oе е в DELL STAB

Answer 1

30 sin ( 2500+ 40.7) 6) Let the period be Ts. 30 sin (25011 (+ +T) +0.7) = 30 sin (2507 +017) : 2500T = 20 7 T = 2750 = 0.098.5 = 8 ms c) i 30 sin (2500+07) W - 25on i frequency of = 250r = 125 H2 250R --125 H2 20 d 30 sin( 250n+ +0.4) when t=0 i= 30 sin (0.7) vi Phase angle = 0.70 18 -0.7 x 180 = 40.0

e) - 30 si 2500+ +0.7) when t= 3.96 - 30 sin (205 i= 30 sin (2500x3.9 +0.7) = 30 sinf - 30X(-) 0.644 =-19.32 A ir 30 sin (25out +0.7) when the current tirst reaches its max. value 250 tit +0.7 = 1/2 => 250 nt = 0.87 7 t = 11x153 sec =lilms