1. A step-up transformer increases
(A) voltage
(B) current
(C) power
(D) frequency
2. The effect of increasing the length of the air gap in an induction motor will be to increase
(A) power factor
(B) speed
(C) magnetising current
(D) air-gap flux
3. The combined resistance of two equal resistors connected in parallel is equal to
(A) One half the resistance of one resistor
(B) Twice the resistance of one resistor
(C) Four times the resistance of one resistor
(D) One fourth the resistance of one resistor

4. The demand factor for the electrical system is the ratio of
(A) Maximum demand to connected load
(B) Maximum demand to average load
(C) Average power to maximum power
(D) Relative power to total power
5. A DC series motor is best suited for driving
(A) Lathes
(B) Cranes and hoists
(C) Shears and punches
(D) Machine tools
6. A network that does not have either voltage or current sources is called
(A) Active network
(B) Passive network
(C) Resistive network
(D) Dummy network

7. The forbidden energy gap in semiconductors
(A) lies just below the valence band
(B) lies just above the conduction band
(C) lies between the valence band and the conduction band
(D) is the same as the valence band
8. The ripple factor of a power supply is a measure of
(A) its voltage regulation
(B) its diode rating
(C) purity of power output
(D) its filter efficiency
9. The foundation on which an IC is built is called
(A) an insulator
(B) a base
(C) a wafer
(D) a plate

10. X-ray tubes make use of
(A) Thermionic emission
(B) Secondary emission
(C) High field emission
(D) Photoelectric emission
11. Avalanche breakdown is primarily dependent on the phenomenon of
(A) Collision
(B) Doping
(C) Ionisation
(D) Recombination
12. The main reason why electrons can tunnel through a P-N junction is that
(A) They have high energy
(B) Barrier potential is very low
(C) Depletion layer is extremely thin
(D) Impurity level is low