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VSSC (ISRO) Technician B (Electronic Mechanic) 2012 Official Paper (Held on 22 Dec 2012)

Option 2 : 100 mV

__Concept__:

The voltage gain of an amplifier is defined as the ratio of the output voltage to the input voltage.

Mathematically, this is defined as:

\(V_{gain}=\frac{V_0}{V_{in}}\)

__Calculation__:

Given Vgain = 100

Vout = 10 V

\(100=\frac{10}{V_{in}}\)

\(V_{in}=\frac{10}{100}\)

Vin = 0.1 V = 100 mV