(a) 111V

(b) 90V

(c) 50V

(d) 100V

Answer

[2] A permanent magnet moving coil ammeter has

a coil resistance of 99ohm and Full Scale Deflection(FSD) current of

0.1mA. Shunt resistance is 1 ohm. Current through the meter at 0.5

F.S.D is

(a) 0.007mA

(b) 0.05mA

(c) 0.023mA

(d) 0.1mA

Answer

[3] One single phase wattmeter operating on

230V and 5A for 5 hours makes 1940 revolutions. Meter constant in

revolutions is 400. What is the power factor of the land?

(a) 1

(b) 0.84

(c) 0.73

(d) 0.65

Answer

[4] For power measurement of three phase

circuit by two wattmeter method, when the value of power factor is less

than 0.5 lagging

(a) one of the wattmeters will read zero

(b) both give the same readings

(c) one of the wattmeter connections will have to be reversed

(d) pressure coil of the wattmeter will become ineffective.

Answer

[5] When using ohmmeter, applied voltage is to be disconnected from the circuit because

(a) Voltage source will increase resistance

(b) Current will decrease resistance

(c) the ohmmeter has its own internal battery

(d) non of the above

Answer

[6] Which wave has the least form factor?

(a) Square wave

(b) Rectangular wave

(c) Sine wave

(d) Triangular wave

Answer

[7] With a sweep time 10ms across the screen the approx. horizontal sawtooth frequency will be

(a) 50Hz

(b) 100Hz

(c) 1kHz

(d) 500Hz

Answer

[8] A spring controlled indicating instrument

has a deflection of 90deg for maximum current I. The corresponding

deflection for a gravity controlled instrument is

(a) 90°

(b) 120°

(c) 30°

(d) 0°

Answer

[9] It is found that 10A current passes

through a resistor of 10ohms. The resistor has 5% tolerance . The error

in measurement of current can be as high as 5%. What is max error in

measurement of power, calculated from measured value of I and the

nominal value of resistor?

(a) 100 W

(b) 150W

(c)50W

(d) 200W

Answer

[10] A resistor of 10Kohms with 5% tolerance

is connected in parallel with a 5Kohms resistor of 10% tolerance. What

is the tolerance limit for the parallel network?

(a) 5%

(b) 6.67%

(c) 10%

(d) 8.33%

Answer

[11] The resistance offered to the passage of

an in-varying current by a column of mercury at the temperature of

melting ice of mass 14.4521 gms of uniform cross-sectional area and

length 106.3cm is

(a) Standard ohm

(b) One international ohm

(c) One ohm according to SI units

(d) One ohm according to working standards

Answer