EE MCQ

Related Question

In the given diagram all are NOR Gate . The final output is shown in the figure.

At stage 1 the output will be \overline A \& \overline B

At stage 2 the output will be \overline {\overline A + \overline B } = A.B

And the final output will be \overline {A.B}

Hence for input A & B the output is \overline {AB} in case of Nand gate.

SSC JE Electrical 2019 with solution SET-1
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Hunting occurs in a/an motor

Sudden changes of load on synchronous motors may sometimes set up oscillations that are superimposed upon the normal rotation, resulting in periodic variations of a very low frequency in speed. This effect is known as hunting or phase-swinging.

SSC JE Electrical 2019 with solution SET-1
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Which of the following is the correct relation regarding coupled coils?

Mutual inductance between two coupled coils is given by the relation

M = K√L1L2

Where

L1L2 = Inductance of the coil

K = Coefficient of coupling

When K = 1 coils are said to be tightly coupled and if K is a fraction the coils are said to be loosely coupled.

Here

Kmax =1

Kmin =0

∴ m ≤ (L1 L2 )0.5

SSC JE Electrical 2019 with solution SET-1
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If the copper loss of a transformer at half full load is 400 W, then the copper loss corresponding to full load is

Copper loss is proportional to the square of load current. At half load, load current becomes half as voltage remains the same, so the copper loss will become (1/2)2 i.e 1/4 times of full load copper loss.

At full load copper Loss = I2R

At half load copper Loss = (I/2)2 × R = I2/4 × R

400 = I2/4 × R

I2R = 4 × 400

I2R = Full load copper Loss = 1600 W

SSC JE Electrical 2019 with solution SET-1
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P = ρQHg is the water power equation. Head ‘H’ is measured in meter ‘g’ gravity constant is measured in meter/second square, then the measuring unit of ‘Q’, the flow rate of water is:

P = ρ QHg is the water power equation.

Where

H = heead = meter

g = gravity =m/s2

ρ =density = (kg/m3)

P = power = watt = N-m/sec

Q = water flow rate = m3/sec