GATE 2023 IN – Question 52
The two secondaries of a linear variable differential transformer (LVDT) showed a magnitude of 2 V (RMS) for zero displacement position of the core. It is noted that the phase of one of the secondaries has a deviation of one degree from the expected phase. Other than this deviation, the LVDT is ideal. If the differential output sensitivity of the LVDT is 1 mV (RMS)/1 µm, the output for zero displacement is __________ µm (rounded off to one decimal place).
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Correct answer: 34.5 to 35.5
Explanation
Two 2 V phasors intended to cancel have angular mismatch 1°. Their residual is $2(2)\sin(0.5^\circ)=0.034906$ V, or 34.906 mV. Dividing by 1 mV/μm gives **34.9 μm**.