(Paper) BSNL JTO Model Test Paper For 2009 Examinations

Email Newsletter FREE SMS ALERTS  FACEBOOK , TWITTER

Paper : BSNL JTO Model Test Paper For 2009 Examinations

If the voltage applied across a capacitance is triangular in waveform then the waveform of the current is
a) Triangular
b) Trapezoidal
c) Sinusoidal
d) Rectangular
Answer: d.

One of the following statement which is true for relative dielectric constant is
a) It is dimensionless
b) It is not equal to unity for vacuum
c) It’s value for all substances is less than one
d) None
Answer: a

Pure metals generally have
a) high conductivity and low temperature coefficient
b) high conductivity and large temperature coefficient
c) low conductivity and zero temperature coefficient
d) low conductivity and high temperature coefficient
Answer:a

For small size, high frequency coils, the most common core material is
a) Air
b) Ferrite
c) Powdered ion
d) Steel
Answer: a

For an abrupt junction Varactor diode, the dependence of device capacitance (C) on applied reverse bias (V) is given by
a) C a V1/3
b) C a V-1/3
c) C a V1/2
d) C a V-1/2
Answer: a

A superconductor is a
a) A material showing perfect conductivity and Meissner effect below a critical temperature
b) A conductor having zero resistance
c) A perfect conductor with highest dimagnetic susceptibility
d) A perfect conductor which becomes resistive when the current density through it exceeds a critical value
Answer: 2


When a semiconductor based temperature transducer has a temperature coefficient of –2500 mV/0C then this transducer is indeed a
a) Thermistor
b) Forward biased pn junction diode
c) Reverse biased pn junction diode
d) FET
Answer: b

The location of lightning arrestor is
a) Near the transformer
b) Near the circuit breaker
c) Away from the transformer
d) None
Answer: a

Time constant of an RC circuit increases if the value of the resistance is
a) Increased
b) Decreased
c) Neither a nor b
d) Both a and b
Answer: a

Intrinsic semiconductors are those which
a) Are available locally
b) Are made of the semiconductor material in its purest from
c) Have more electrons than holes
d) Have zero energy gaps
Answer: b

The primary control on drain current in a JFET is exerted by
a) Channel resistance
b) Size of depletion regions
c) Voltage drop across channel
d) Gate reverse bias
Answer: d

The electrical conductivity of metals which is expressed in ohm-1 m-1 is of the order of
a) 1010
b) 105
c) 10-4
d) 10-6
Answer: b

When biased correctly, a zener diode
a) acts as a fixed resistance
b) has a constant voltage across it
c) has a constant current passing through it
d) never overheats
Answer: b

The current amplification factor adc is given by
a) IC/IE
b) IC/IB
c) IB/IC
d) IB/IC
Answer: a

Compared to bipolars, FETs have
a) high input impedance
b) low input impedance
c) same input impedance
d) none
Answer: a

The source-drain channel of JFET is
a) ohmic
b) bilateral
c) unilateral
d) both a and b
Answer: d

Post Your Resume | UPSC Downloads | Aspirants Times Direct Download | Online Book Store