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BuddhaBelly34
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Homework Statement
Time-domain expression for i(t), based on measures above:
Time-domain expression for i(t), based on measured R and L:
Vp-p on 16Ω resistor: 7.25mV "measured above"
Ip-p for resistor: 0.676mA "measure above"
Ip for resistor: .338mA "measured above"
R: 14.8Ω L: 10.1mH "measured R and L"
Source voltage is 5Vp-p 0 off-set at 1kHz
Homework Equations
? The issue is that I need to make the equations I suppose.
The Attempt at a Solution
This is for the measured R and L values:
Ip = Vp/(R + jωL) = 2.5/(14.8 + j2000∏*10.1) = 2.5/(14.8 + j63.5) = 37/622 - j(159/622) = 59E-3 - j256E-3
i(t) = R(cosωt - β)
R = √(x2 + y2) = √((59E-3)2 + ((256E-3)2) = 263E-3
β = tan-1(-256/59) = -77°
i(t) = 0.263cos(2000∏t + 77°)
Some specific issues:
1. How in the world can i(t) = Rcos(ωt - β)? Wouldn't that make voltage lag current which shouldn't happen when an inductor is in the circuit?
2. When I do the problem with
Vp-p on 16Ω resistor: 7.25mV "measured above"
Ip-p for resistor: 0.676mA "measure above"
Ip for resistor: .338mA "measured above"
should I be using Vp = 7.25E-3/2 or Vp = Vsource p-p/2? The instructions in the lab manual and the slides from the professor that wrote the manual where not clear.
Thanks in advance!
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