engineering recuitment GATE IN Test Series 2023-24 Mock Test Electrical and Electronics Measurements Q Meter
A constant rms voltage of frequency 3 MHz is applied to a coil of inductance L and resistance R, a calibrated variable capacitor C, and a thermojunction all in series. The uncalibrated ammeter is formed to shown the same scale reading I for the two values of C namely 37 and 45 PF one being below and the other above the capacitance Co needed to produce maximum current.
The capacitor is now adjusted to a value Co, and an added series resistance of 75 Ω is found to reduce the current to previous value of I. Determine the value of R.
(Assume that the resonance curve be peaked and symmetrical)1
70.8 Ω
2
72.4 Ω
3
84.1 Ω
4
91.3 Ω