1. State whether the following statements are True or False:

The specific resistance depends upon the area of cross-section of the conductor only.

The unit of magnetic field is Wb/m^2.

Norton's theorem is not applicable to a.c. circuits.

The phase angle between voltage and current is 90° in case of purely resistive circuit.

BJT can be used as switch.

According to De Morgan's first theorem

The maximum data rates for RS-232 is 19·2 k baud or bits per second.

Explain the factors affecting the resistivity of conductors. What are the limitations of Ohm's law?

A coil with 250 turns carries a current of 2 and produces a flux a of 0·3 mWh. When this current is reduced to zero in 2 milliseconds, the voltage induced in a nearby coil is 60 volts. Calculate

self-inductance of each coil, and

mutual inductance between the coils. Assume coefficient of coupling 0·7.

State the Thevenin's theorem with the help of a suitable example.

Explain the principle of operation of a transformer and draw the equivalent circuit of a transformer referred to the secondary side.

Explain the principle of operation of a three-phase induction motor. Also, derive the relation between. rotor frequency and stator frequency.

Find the

frequency of resonance,

current and power factor at resonance, and

Q-factor at resonance, for the circuit shown in Figure 1.

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Explain the I characteristics of Zener diode and explain its working as a voltage regulator.

What is the full form. of MODEM? What are the basic functions of MODEM

Draw the circuit diagram of an NPN junction transistor CE configuration and describe the static input and output characteristics.

Convert the following decimal numbers into binary:

35

127

Draw the block diagram of a computer and explain each block.

Write short notes on the following:

TRIAC

IGBT