Match the following : Codes :List – I List – II a. LED i. Heavily doped b. Avalanche Photodiode ii. Coherent radiation c. Tunnel diode iii. Spontaneous emission d. LASER iv. Current gain
a-i, b-ii, c-iii, d-iv
The four bridges pair with their four uses in the order printed: a-i, b-ii, c-iii, d-iv — option 1.
| Bridge | Measures | Best suited to |
|---|---|---|
| a. Maxwell | Inductance | Medium-Q coils, 1 < Q < 10 |
| b. Hay | Inductance | High-Q coils, Q > 10 |
| c. Schering | Capacitance | Precision work, insulation testing |
| d. Wien | Frequency | Also a filter and oscillator network |
Maxwell against Hay — the distinction the question turns on. Both measure inductance by balancing an unknown coil against a standard capacitor, which is convenient because capacitors are far easier to make accurately than inductors. The difference is where the capacitor sits.
Maxwell's bridge uses a capacitor in parallel with a resistor. Its balance gives
\(L_{x}=R_{2}R_{3}C_{1},\qquad R_{x}=\dfrac{R_{2}R_{3}}{R_{1}}\)
For a high-Q coil, \(R_{1}\) would have to be impractically large, so the method suits medium Q.
Hay's bridge puts the capacitor in series with its resistor instead, which makes the required resistance small for a high-Q coil — exactly the opposite dependence. Its balance carries a \(1/Q^{2}\) correction term that becomes negligible above Q = 10, so the two bridges divide the range between them.
c — why Schering is the precision capacitance bridge. It measures not only capacitance but the dissipation factor \(D=\tan\delta=\omega C R\), which is the quantity that matters when testing insulation, cables and high-voltage bushings for deterioration. Its balance is independent of frequency, and it works at high voltage — both essential for that application.
d — Wien for frequency. Its balance condition depends on frequency,
\(f=\dfrac{1}{2\pi RC}\)
so with known R and C the balance point measures the source frequency — and the same network, used as the positive-feedback arm of an amplifier, generates that frequency in the Wien-bridge oscillator.
Hence, the correct code is a-i, b-ii, c-iii, d-iv.
Similar Questions
Match the following :
List – I List – II a. Miller sweep in CRO i. storage oscilloscope b. Study of transients ii. integrator c. Korotkoff sound iii. phase measurement d. Lissajous pattern iv. blood pressure Codes :
Assertion (A) : Oscilloscope provides graphical representation of time varying signals.
Reason (R) : Bandwidth is the limitation of oscilloscope.
In a normal ECG wave form, which wave has the maximum amplitude ?
Match the following :
List – I List – II a. Storage oscilloscope i. Pulse testing b. Sampling oscilloscope ii. Time domain c. High frequency oscilloscope iii. Long term memories d. Low frequency oscilloscope iv. Servo system analyzer Codes :
Assertion (A) : The shift in the position of the bright spot on the CRO screen per unit change of voltage across the deflection plates is called deflection sensitivity.
Reason (R) : The path traveled by the spot on a CRO screen during the retrace time is called retrace path.
A current of 300 µA produces FSD in an instrument whose coil resistance is 75 Ω. What will be the value of shunt resistors if the instrument is to measure current of 5A ?
The resistor value required to use a 0-1 mA meter with an internal resistance of 125 Ω for a 0-1 V meter will be :
There are number of distinct advantages of the digital storage oscilloscope as given below :
(A) A waveform to be stored is digitized
(B) The waveform is stored in a digital memory
(C) The stored waveform can be displayed as and when required
(D) The cost is reduced as compared to conventional CRTChoose the correct answer from the options given below :
Read the following statements with respect to a Wein bridge :
(A) It is an AC bridge to measure frequency
(B) It is a DC bridge to measure amplitude
(C) It is used as frequency determining element
(D) It is used as band pass filter
(E) It is used as Notch filterChoose the correct answer from the options given below :
Match List - I with List - II.
List - I List - II (A) Electrical resistance (I) °C/W (B) Thermal resistance (II) W (C) Time constant (III) RC (D) Rate of heat transfer (IV) V/A Choose the correct answer from the options given below :
Important Questions from Miscellaneous
The magazine in which Mahatma Gandhi mentioned what he wanted the Constitution to do is:
Which gas shields the surface of the earth from ultraviolet radiation from the sun?
Which event is marked as an Intangible Cultural Heritage of Humanity by UNESCO?
Who has been conferred with the rank of the Commander of the Order of the British Empire in 2018?
Who directead the film ‘Bhuvan Shome’?
