Class 12 Physics - Chapter Semiconductor Electronics NCERT Solutions | Two amplifiers are connected one after t
Two amplifiers are connected one after the other in series (cascaded). The first amplifier has a voltage gain of 10 and the second has a voltage gain of 20. If the input signal is 0.01 volt, calculate the output ac signal.
Given that,
Voltage gain of the first amplifier, V 1 = 10
Voltage gain of the second amplifier, V 2 = 20
Voltage of input signal, V i = 0.01 V
Voltage of output AC signal = V o
The total voltage gain of a two-stage cascaded amplifier is given by the product of voltage gains of both the stages,
i.e., V = V 1 × V 2 = 10 × 20 = 200
It can be calculated by the relation: V = Vo/Vi
V 0 = V × V i = 200 × 0.01 = 2 V
Therefore, the output AC signal of the given amplifier is 2 V.
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