1. An alternating current is given by the formula
I = 30 sin (50 t + 0.26) amps
a) Find the amplitude, periodic time, frequency, and phase angle
b) Find the value of the current at 18ms
c) Find the time at which the current first reaches 20 amps
d) Plot the curve between 0 and 20ms
Amplitude = 30
frequency
"50=\\omega=2\\Pi f"
"f=50\/2\\Pi=7.957747155 Hz"
periodic time
"T=1\/f=1\/7.957747155=0.125663706 seconds"
"=125.663706ms"
phase angle
"=0.26radians"
"=0.26*180^{\\circ} \/\\pi)=14.8969 \\, degrees"
at 18 ms "I=30sin(50(0.018)+0.26)=27.504"
"20=30sin(50t +0.26)"
"2\/3=sin (50t+0.26)"
"41.8103149=50t+0.26"
"t=0.831006297 seconds"
graph
Comments
Dear VPM, we have already changed that formula, please read a solution of the question.
Second mistake at 18 ms I=30sin(50(0.18)+0.26)=4.827I=30sin(50(0.18)+0.26)=4.827 i wanted to know if this equation is right because when I write it in my calculator it comes with a different number
Dear Vm, thank you for correcting us.
Second mistake at 18 ms I=30sin(50(0.18)+0.26)=4.827I=30sin(50(0.18)+0.26)=4.827 i dont get this when i do the working out
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