MCQ on Electronics and Communication Engineering

13-The term critical angle describes
(A) The point at which light is refracted
(B) The point at which light becomes invisible
(C) The point at which light has gone from refractive mode to the reflective mode
(D) The point at which light has crossed the boundary layers from one index to another
 
14-Which of the following material is not used to make strain gauges?
(A) Nichrome
(B) Pure platinum
(C) Bronze
(D) Karma alloy
 
15-A Remote Terminal Unit (RTU) in a telemetry system is used for
(A) Providing power to the remote sensors
(B) Converting the output of the sensor to digital data and transmit to the base station
(C) Managing the health condition of the sensors
(D) Remote control the base station
 
16-All CDMA based technologies 2G and 3G have _____ handovers.
(A) Soft handover
(B) Hard handover
(C) Blind handover
(D) Soft and Hard handover
 
17-Which of the following is not a mode of operation of SCR?
(A) Forward blocking mode
(B) Forward conduction mode
(C) Reverse blocking mode
(D) Reverse conduction mode
 
18-Which of the following is not an essential characteristic of robot?
(A) Sensing
(B) Human friendly
(C) Movement
(D) Intelligence
 
19-The minimum current that can pass the circuit in order for the SCR to remain in the ON state is
(A) Latching current
(B) Reverse saturation current
(C) Holding current
(D) Leakage current
 
20-In electromagnetic radiation spectrum, the wavelength range for thermal radiation is
(A) 0.1 μm to 100 μm
(B) 0.001 μm to 0.01 μm
(C) 100 μm to 1000 μm
(D) 1000 μm to 2000 μm
 
21-The damping ratio is strictly less than 1 for a system. Then the system is
(A) Under damped
(B) Over damped
(C) Critically damped
(D) Undamped
 
22-Which of the following is TRUE for an OPAMP?
(A) Low input resistance
(B) Very high output resistance
(C) Very high input resistance
(D) Low open circuit voltage gain
 
23-Linear system obeys
(A) Super position theorem
(B) Maximum power transfer theorem
(C) Thevenin’s theorem
(D) Norton’s theorem
 
24-Ultrasound devices operates with frequencies in the range
(A) 20 KHz – several GHz
(B) 20 KHz – several MHz
(C) 20 Hz – 20 KHz
(D) 20 Hz – 2000 Hz
 
25-A switching device that converts fixed DC input to a variable DC output voltage directly is
(A) Chopper
(B) Inverter
(C) Regulator
(D) Stabilizer
 
ANSWERS:
13-(C), 14-(C), 15-(B), 16-(A), 17-(D), 18-(B), 19-(C), 20-(A), 21-(A), 22-(C), 23-(A), 24-(A), 25-(A)