An equipotential surface is a surface in an electric field such that all points on it are at the

A)Same potential 
B)Different potential 
C)Different frequency 
D)Same frequency

In a.c. voltage regulator with R-L load

A)the current leads the voltage
B)current will lead or lag the voltage depending on the L/R ratio 
C)the voltage lags the current
D)the voltage leads the current

Load voltage in a d.c. chopper circuit is given by / d.c.

A)d.c. supply voltage /duty cycle 
B)Duty cycle X d.c. supply voltage 
C)Duty cycle/ d.c. supply voltage
D)1/(duty cycle X d.c. supply voltage)

A thermistor has a resistance of 3.98 Kilo Ω at 0 °C and 0.794 Kilo Ω at 50 °C. If the relation between resistance and temperature is RT = a RO e b/T, the value of constant b is

A)2845

B)1845

C)4845

D)3845

Zener breakdown occurs due to breaking of covalent bonds by the strong electric field set up in the depletion region by the

A)Reverse coupling 
B)Reverse voltage 
C)Forward current 
D)Forward voltage

A strain gauge with a resistance of 250 Ω undergoes a change of 0.15 Ω during a test. The strain is 1.5 x 10-4. The gauge factor is

A)4
B)6
C)3
D)1

For a moving charge Q in the presence of both electric and magnetic fields, the total force on the charge is given by

A)F = Q(B + μ x E)
B)F = Q(E - μ x B)
C)F = Q(B - μ x E)
D)F = Q(E + μ x B)

In a 132kV circuit breaker the bushing to ground capacitance is 0.01 microFarad and the transformer inductance succeeding the circuit-breaker is 4H. What will be the voltage appearing across the poles of circuit-breaker as it breaks a magnetising current of 15A flowing in the transformer?

A)300 kV
B)144 kV
C)363 kV
D)282 kV

A 1000 kHz carrier is modulated with 800 Hz audio sine wave, the frequencies present in the output will be

A)1000, 1000.8 kHz
B)999.2, 1000.8 kHz 
C)999.2, 1000 kHz 
D)1000, 1800 kHz 

Which of the following law states that the magnetic field intensity dH produced at a point P, by the differential current element Idl is proportional to the product of Idl and the sine of the angle α between the element and the line joining P to the element and is inversely proportional to the square of the distance R between P and the element?/

A)Ampere's circuit law 
B)Gauss's law 
C)Snell's law 
D)Biot-Savart's law

Converting the signed decimal -1 to 8 bit 2's complement number will result in

A)000000 01
B)111111 10
C)111111 11
D)011111 11

Master-slave J-K flip-flop is used to

A)Eliminate race around condition
B)Improve its reliability
C)Reduce power dissipation
D)Increase its clock frequency

When is the READY signal sampled or checked by the 8085 microprocessor?

A)At the end of each machine cycle
B)At the 2nd state of every machine cycle
C)At the end of each instruction cycle
D)At the 1st state of every machine cycle

Two point charges - 4 μC and 5 μC are located at (1 , 0 , 3) and (1, 4, - 2) respectively, then the potential at (1, 0, 1) assuming zero potential at infinity will be (consider ε0 = 10-9/36π)

A)-9 kV
B)-6 kV
C)6 kV
D)9 kV

A 3-phase, half wave controlled rectifier is connected to a 220V source. If the delay angle is 45 degree and the load resistance is 10 Ohm, what will be the average power dissipation in SCR, if SCR has a forward voltage drop of 1 V?

A)2.5 W
B)4.5 W
C)1.5 W
D)3.5 W

A diffraction pattern of a cubic crystal of lattice parameter a = 3.16 A⁰ is obtained with monochromatic X-ray beam of wavelength 1.54 A⁰, the first line on this pattern was observed to have θ = 30⁰, the interplanar spacing will be

A)1.54 A⁰
B)3.1 A⁰
C)11.2 A⁰
D)9.3 A⁰

The induced dipole moment is proportional to the field strength and the proportionality factor αe is called

A)Electronic polarizability
B)Protonic polarizability
C)Electronic field strength
D)Nuclear polarizability

A complex wave of r.m.s. value 240 V has 20% 3rd harmonic content and 2% 5th harmonic content then the approximate r.m.s. value of the fifth harmonic will be

1. 5.7 V
2. 4.7 V
3. 3.7 V
4. 2.7 V

The impedance of a 100 Ω resistor in series with a 10 mH inductor in the s-domain will be

A) 10+1002 s Ω
B) 10+100−2s Ω
C) 100+10−2 s Ω
D) 100+102 s Ω

The addressing mode used in instruction MOV A, B is

A)Implied
B)Immediate
C)Direct
D)Register