Question

For a Light–Emitting–Diode (LED) which of following statements is wrong? 

(1) It is a heavily doped p–n junction emitting spontaneous radiations when forward biased 

(2) When forward biased the concentration of minority charge carriers increases rapidly on the sides of the junction boundary 

(3) The energy released due to recombination of electrons and holes is mostly transferred into the thermal energy of lattice vibrations 

(4) LED emits light when it is reverse biased

Answer 1

Correct option: (4) LED emits light when it is reverse biased

Explanation: 

LED emits light when it is forward biased. As forward current increases intensity of light emitted by LED also increases. When LED is reverse biased it emits no light. The LED is damaged when it is reverse biased.