Which one of following band is completely filled in case of conductors ?

A. Conduction band
B. Fermi band
C. Valence band
D. Forbidden band

The value of resistivity for insulator is of the order of____________?

A. 105 ohm metre
B. 106 ohm metre
C. 107 ohm metre
D. 108 ohm metre

Forward current through a semi conductor diode circuit is due to____________?

A. minority carriers
B. majority carriers
C. holes
D. electron

Which one of the following is not a donor impurity ?

A. antimony
B. phosphorus
C. aluminium
D. arsenic

In full wave rectification the output D.C. voltage across the load is obtained for_____________?

A. The positive half cycle of input A.C.
B. The negative half cycle of input A.C.
C. The complete cycle of input A.C.
D. All of the above.

In half-wave rectification the output D.C. voltages is obtained across the load for_______________?

A. The negative half cycle of A.C.
B. The positive half cycle of A.C.
C. The positive and negative half cycles
D. Either positive or negative half of A.C.

The device used for conversion of D.C. to A.C. is called______________?

A. Converter
B. A rectifier
C. Inverter
D. Oscillator

The specially designed semi-conductor diodes used as fast counters in electronic circuits are______________?

A. The light emitting diodes
B. Photo diodes
C. Photo voltaic cell
D. Solar cells.

Which one of the following has the greatest energy gap ?

A. insulator
B. conductor
C. semi conductor
D. any of above

Thermions are________________?

A. protons
B. positrons
C. electrons
D. photons