BPHC 0002 Quiz 1

The maximum efficiency of full wave rectification is

• 40.6% .

• 100% c

• 81.2%

• 85.6%

A zener diode is used as ……………

• rectifier

• voltage regulator

• filter

• none

A LED emits visible white light when its

• junction is reversed biased

• depletion layer widens

• holes and electrons recombine

• junction becomes hot

Which among these is NOT the property of a semiconductor?

• Four electrons in the valence band forming covalent bonds

• At 0 Kelvin semiconductor acts like an insulator

• Semiconductors have two type of charge carriers

• Semiconductors are temperature insensitive

Fermi level of intrinsic semiconductor lies

• Middle of band gap

• Close to conduction band

• Close to valence band

• None of the above

Heating a extrinsic semiconductor results

• Intrinsic semiconductor

• More extrinsic

• N type becomes p type and vice versa

• None of the above

Which diode shows negative resistance

• Tunnel diode

• Zener diode

• Photo diode

• Any p n diode

Photo diode works on

• FForward Bias

• Reverse bias

• Any of the bias

• Depends on the temperature

The width of the depletion region increases

• Reverse bias

• forward bias

• No biasing

• Upon heating

The conductivity of semiconductor increases if

• We increase the temperature

• We decrease the temperature

• Suddenly decrease the temperature

• Not possible by varying the temperature. Only by doping, it is possible