Electronics and Communication Engineering - Electronic Devices and Circuits

46.
Photoelectric emitters in photo tubes are generally made of
alkali metals
metals
semiconductors
metal and semiconductors
Answer: Option
Explanation:
No answer description is available. Let's discuss.

47.

Assertion (A): Power transistors are more commonly of silicon npn type.

Reason (R): The fabrication of silicon npn transistors is easy.

Both A and R are true and R is correct explanation of A
Both A and R are true but R is not a correct explanation of A
A is true but R is false
A is false but R is true
Answer: Option
Explanation:
No answer description is available. Let's discuss.

48.
In N-type semiconductor
electrons are majority carriers while holes are minority carriers
electrons are majority carriers while holes are majority carriers
both electrons as well as holes are majority carriers
both electrons as well as holes are minority carriers
Answer: Option
Explanation:
No answer description is available. Let's discuss.

49.
The addition of n type impurity to intrinsic material creates allowable energy levels.
slightly below conduction band
slightly above conduction band
slightly below valence band
slightly above valence band
Answer: Option
Explanation:
No answer description is available. Let's discuss.

50.
Which of the following elements act as donor impurities?
  1. Gold
  2. Phosphorus
  3. Boron
  4. Antimony
  5. Arsenic
  6. Indium
Select the correct answer using the codes given below:
1, 2, 3
1, 2, 4, 6
3, 4, 5, 6
2, 4, 5
Answer: Option
Explanation:
No answer description is available. Let's discuss.