A transistor is used in an amplifier circuit in common emitter mode. If the base current changes by 100μA, it brings a change of 10mA in collector current. If the load resistance is 2kΩ and input resistance is 1kΩ, the value of power gain is \(x×10^4\). The value of x is _______.
Correct Answer: 2
Solution and Explanation
The correct answer is: 2
Power gain
\(=[\frac{\triangle{ic}}{\triangle{iB}}]×\frac{R_0}{R_i}\)
\(=[\frac{10^{-2}}{10^{-4}}]×\frac{2}{1}\)
= 2 × 104
\(⇒ x = 2\)
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Concepts Used:
Amperes circuital law
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According to the second equation, if the magnetic field is integrated along the blue path, then it is equal to the current enclosed, I.
The magnetic field doesn’t vary at a distance r because of symmetry. The path length (in blue) in figure 1 has to be equal to the circumference of a circle,2πr.
