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Q.7:- An n-channel silicon (= 1.1 eV) MOSFET was fabricated using n poly silicon gate and the threshold voltage was found to be 1 V. Now, if the gate is changed to p poly-silicon, other things remaining the same, the new threshold voltage should be

(a) –0.1 V(b) 0 V(c) 1.0 V (d) 2.1 V

Q.8:- Scintillation is

(a)

Variation of physical dimensions under the influence of magnetic field.

(b)

Deionization of gases under low pressures.

(c)

Production of flashes of light by some substances when struck by alpha, beta of gamma rays.

(d)

Change in dielectric constant of substances with change in humidity.

Q.9:- Which of the following statements is true?

(a)

ROM is Read /Write memory.

(b)

PC points to the last instruction that was executed.

(c)

Stack works on the principle of LIFO.

(d)

All instructions affect the flags.

Q.10:- In which range the cost of a synchronous motor is likely to be comparable to the cost of induction motor?

(a)

Low H.P., high speed.

(b)

High H.P., low speed.

(c)

High H.P., high speed.

(d)

Low H.P., low speed.

Q.11:- which one of the theories given below is related to the theory of the thermocouple?

(a) Piezoelectric effect (b) Skin effect(c) See back effect(d) Faraday’s Law

Q.12:- For the purpose of analysis exact equivalent circuit of a transformer is usually replaced by an approximate equivalent circuit. In doing so errors introduced due to winding copper loss and core loss are of differential nature. Due to this the analysis by approximate equivalent circuit gives fairly satisfactory results. Under the circumstance, which one of the following is correct in respect of losses referred to approx. Equivalent circuit?

(a)

This accounts for somewhat greater primary winding copper loss and more cores less core loss.

(b)

This accounts for somewhat lesser primary winding copper loss and more core loss.

(c)

This accounts for somewhat greater secondary winding copper loss and less core loss  

(d)

This accounts for somewhat lesser secondary winding copper loss and more core loss.

Q.13:- Consider the following statements: In a 3-phase induction motor connected to a 3-phase supply; if one of the lines suddenly gets disconnected, then the

1.

Motor will come to a standstill.

2.

Motor will continue to run at the same speed with line current unchanged.

3.

Motor will continue to run at a slightly reduced speed with increased line current.

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