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ESE Electrical 2013 Paper 2: Official Paper

Option 4 : 10^{7}

CT 3: Building Materials

2962

10 Questions
20 Marks
12 Mins

**Concept:**

**Common mode rejection ratio(CMRR): **It is the “ratio of the differential voltage gain (A_{d}) to the common-mode voltage gain (A_{cm})”.

The higher the value of CMRR the better is the matching between two input terminals and smaller is the output common-mode voltage.

CMRR = \( \frac{{{A_d}}}{{{A_{cm}}}}\)

It is infinity ∞ for the ideal op-amp.

**Calculation:**

Given that, common-mode gain = 0.01

Differential mode gain = 105

CMRR=\(\frac{{{{10}^5}}}{{0.01}}\) = 10^{7}.