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Given below are two statements:
Statement I: PN junction diodes can be used to function as transistor, simply by connecting two diodes, back to back, which acts as the base terminal.
Statement II: In the study of transistor, the amplification factor β indicates ratio of the collector current to the base current. In the light of the above statements, choose the correct answer from the options given below:
- Statement I is false but Statement II is true
- Both Statement I and Statement II are true
- Both Statement I and Statement II are false
- Statement I is true but Statement II is false
Correct answer: Statement I is false but Statement II is true
Solution
Statement I is false: two PN diodes connected back to back do not behave as a transistor (a transistor requires a single thin, lightly doped base shared between the junctions). Statement II is true: the current amplification factor beta = collector current / base current. So I is false but II is true.
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