Instrumentation Engineering
GATE IN format:nat PYQs
Build your understanding with focused practice from past exam papers.
Questions 21–30 of 270. Imported answers require independent review unless marked reviewed.
Question 54
Open questionINNAT2 marksNeeds review
Let
represent the discrete time Fourier transform of a 4-length sequence
, where
,
,
, and
.
is sampled at
to generate a periodic sequence in
with period 3, where
represents an integer. Let
represent another sequence such that its discrete Fourier transform
is given as
for
. The value of
is_____ (in integer).Log in to check the answer
You can attempt this question now. Sign in to view the answer key, explanations and discussion.Log in to check answerQuestion 55
Open questionINNAT2 marksNeeds review
A schematic of a Michelson interferometer, used for the measurement of refractive index of gas, is shown in the figure. The transparent chamber is filled with a gas of refractive index
, where
, at atmospheric pressure. If a 532 nm laser beam produces 30 interference fringes on the screen, then the number of fringes produced by a 632.8 nm laser beam will be ____ (rounded off to one decimal place).Note: Assume that the effect of beamsplitter width is negligible. The setup is placed in air medium with refractive index equal to 1.

Log in to check the answer
You can attempt this question now. Sign in to view the answer key, explanations and discussion.Log in to check answerQuestion 56
Open questionINNAT2 marksNeeds review
Consider an AC bridge shown in the figure with
,
,
,
, and a detector
. The source voltage is
. At the bridge balance condition, the frequency of the excitation source
is ________ kHz (rounded off to two decimal places).

Log in to check the answer
You can attempt this question now. Sign in to view the answer key, explanations and discussion.Log in to check answerQuestion 57
Open questionINNAT2 marksNeeds review
An air filled parallel plate electrostatic actuator is shown in the figure. The area of each capacitor plate is 100 μm × 100 μm. The distance between the plates
μm when both the capacitor charge and spring restoring force are zero as shown in Figure (a). A linear spring of constant k = 0.01 N/m is connected to the movable plate. When charge is supplied to the capacitor using a current source, the top plate moves as shown in Figure (b). The magnitude of minimum charge (Q) required to momentarily close the gap between the plates is ______×
C (rounded off to two decimal places).Note: Assume a full range of motion is possible for the top plate and there is no fringe capacitance. The permittivity of free space is
F/m and relative permittivity of air (
) is 1.

Log in to check the answer
You can attempt this question now. Sign in to view the answer key, explanations and discussion.Log in to check answerQuestion 58
Open questionINNAT2 marksNeeds review
The resistance of a thermistor is measured to be 2.25 kΩ at 30 °C and 1.17 kΩ at 60 °C. Its material constant
is __________ K (rounded off to two decimal places).Log in to check the answer
You can attempt this question now. Sign in to view the answer key, explanations and discussion.Log in to check answerQuestion 59
Open questionINNAT2 marksNeeds review
A feedback control system is shown in the figure.

The maximum allowable value of
such that the output
, due to any step disturbance signal
, becomes zero at steady-state, is ________ (in integer).Log in to check the answer
You can attempt this question now. Sign in to view the answer key, explanations and discussion.Log in to check answerQuestion 60
Open questionINNAT2 marksNeeds review
The circuit given in the figure is driven by a voltage source
V. The system is operating at a frequency of 50 Hz. The transformers are assumed to be ideal. The average power dissipated, in W, in the 50 kΩ resistance is ______ (rounded off to two decimal places).

Log in to check the answer
You can attempt this question now. Sign in to view the answer key, explanations and discussion.Log in to check answerQuestion 61
Open questionINNAT2 marksNeeds review
In the circuit shown, the galvanometer (G) has an internal resistance of 100 Ω. The galvanometer current
is ______ μA (rounded off to the nearest integer).

Log in to check the answer
You can attempt this question now. Sign in to view the answer key, explanations and discussion.Log in to check answerQuestion 62
Open questionINNAT2 marksNeeds review
A series RLC circuit resonates at 750 rad/s for inductance L = 20 mH and resistance R = 10
. The uncertainties in the measurement of L and R are 0.8 mH and 0.3
, respectively. The percentage uncertainty in the measurement of quality factor is ______% (rounded off to one decimal place).Log in to check the answer
You can attempt this question now. Sign in to view the answer key, explanations and discussion.Log in to check answerQuestion 63
Open questionINNAT2 marksNeeds review
In the circuit shown, the switch is opened at
s. The current
at
ms is ____________ mA (rounded off to two decimal places). 
Log in to check the answer
You can attempt this question now. Sign in to view the answer key, explanations and discussion.Log in to check answer