Question

In a transistor,
(A) Length of emitter is greater than that of collector
(B) Length of collector is greater than that of emitter
(C) Both emitter and collector have same length
(D) Any one of emitter and collector

Answer 1

Hint : To answer this question we must know what a transistor is. A transistor is a semiconductor device which can transfer a weak signal from a low resistance circuit to a high resistance circuit. In simple words we can regulate and amplify electrical signals such as voltage or current.

Complete step by step solution:
Transistors are considered special because they allow us to control how much current flows through a circuit which can be achieved by controlling the voltage across two of the transistors leads. Each transistor consists of three leads.
Transistors have three terminals which are named as emitter, collector and base. The functions of each of these terminals are described below:
Emitter –The emitter is always forward biased with respect to the base so that it supplies the majority charge carrier to the base. The emitter of a transistor is highly doped and moderate in size.
Collector – In a transistor, collector is the section that collects the majority of the charge carrier supplied by the emitter. The collector-base junction is always reverse biased. The collector section of the transistor is moderately doped, but larger in size hence it can collect most of the charge carrier supplied by the emitter.
Base – It is the middle section of the transistor. The base forms two circuits, they are the input circuit with the emitter and the output circuit with the collector. The base of a transistor is lightly doped and also very thin due to which it offers the majority charge carrier to the base.

Hence the correct option is B where the length of collector is greater than that of emitter

Note:
We must note that the size or the length of the collector is large in comparison to the emitter to dissipate the heat. Whereas the base is very small in comparison to both collector and emitter. A transistor is a three-layered semiconductor device in which one type of semiconductor, either P-type or N-type is sandwiched between two other similar types of semiconductors.