Optimum Fusing A sensitive instrument that can be modeled by the series RLC circuit shown in Figure P7–85 is to be protected by a fuse. The voltage across the capacitor is vCðtÞ ¼ e10tðcos 103t þ 0:0971sin 103tÞ uðtÞ V The peak current was found to occur at about 13 ms after t ¼ 0.

Engineer A suggests a 1-mA fuse, Engineer B suggests a 5-mA fuse while Engineer C suggests a 10-mA fuse. The criterion is to select a fuse that is closest to the peak value of current expected without blowing. Which engineer is correct? Provide evidence for your decision.

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1u(t) V is(t) w + I +vc(t)- Fuse 902 92.5 F 102 1 H Instrument FIGURE P7-85