# An amplifier circuit has a voltage gain of 500. If the output voltage is 5 V, then the input voltage is:

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DSSSB JE EE 2019 Official Paper (Held on 5 Nov 2019)
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1. 1 / 2500 V
2. 2500 V
3. 100 mV
4. 10 mV

Option 4 : 10 mV

## Detailed Solution

Concept:

The voltage gain (Av) for an amplifier is defined as the ratio of the output voltage to the input voltage, i.e.

$$A_v=\frac{V_0}{V_{in}}$$

V0 = Output voltage

Vin = Input voltage

Calculation:

Given: Av = 500, and V0 = 5 V

$$500=\frac{5}{V_{in}}$$

Vin = 1/100 V

Vin = 10 mV
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