Question

Which of the following is not the advantage of semiconductor devices in the electron tubes?
A. Unlimited life
B. Greater efficiency
C. No-warning up time for switching
D. Low consumption of power for cathode heating.

Answer 1

Hint: Semiconductors are materials having conductivity between insulators and conductors, their conductivity increases with an increase in the temperature. Examine each option with the possible usage of these materials and their associated disadvantages to give the correct answer.

Complete answer:
As we know semiconductor is materials which have a conductivity between conductor and insulator they can be pure elements such as silicon germanium or compounds. Let’s discuss the advantages and disadvantages of semiconductors. The advantages of semiconductors are the greater efficiency,
It consumes low power as it has no filament.
It has no warning up time for the switching because they require low voltage. But the disadvantage of semiconductor in the electron tubes is that it has a limited lifetime.
The reason for the incorrect options (b, c, d) is that all the incorrect options are the advantages of the semiconductors, and option (a) is the disadvantage of semiconductors in electron tubes.

So, the correct answer is “Option A”.

Additional Information:
Semiconductors act like an insulator at zero Kelvin temperature on increasing the temperature it works as conductor they can be classified as an intrinsic and extrinsic semiconductor.

Note:
Intrinsic semiconductors are not used to make electronic devices because of their low electric conductivity and thus lower efficiency. The conduction of intrinsic semiconductors is temperature dependent, which is not a physical quantity that is kept high for any electronic device, due to high energy loss. Additionally, read the question very carefully as it has been framed for disadvantages and not advantages. Students must not get confused while answering.