Question

a pn junction cannot be used as
a)rectifier
b)LED
c)amplifier
d)detector

Answer 1

a pn junction cannot be used as

a)rectifier

b)LED

c)amplifier

d)detector

Amplifier

A diode just regulates the flow of current but it can't alter the rate of flow of current

For instance modulating its frequency and Amplitude.

hope it helps

Answer 2

A p-n junction can not be used as an amplifier (option-c).

• p-n junction is also known as a diode.
• It is a device that is composed of p-type and n-type semiconductors.
• Its half part is made up of p-type semiconductor and another half part is made of n-type semiconductor.
• Its working principle is based on forward biasing and reverse biasing.
• It has various applications like it is used in making rectifiers, which converts A.C. current into D.C. current.
• It is used in making LEDs ( light-emitting devices).
• Its working principle is also used in making detectors.
• But, it is not used in making amplifiers, because the p-n junction does not increase or decrease the input signal and it does not amplify the signal.