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The LED in the circuit shown below will be on if ν_i is:

1. > 10 V
2. < 10 V
3. > 5 V
4. < 5 V

Correct Option: C

In the given op-amp circuit is working in open-loop mode, therefore output will be either + V_sat or – V_sat , and in order to glow LED, output voltage must be positive and this can be achieved by making noninverting terminal voltage greater than the inverting terminal voltage.
Inverting terminal voltage is

– =	10	(+ 10 V) = + 5 V
	10 + 10

Hence i > 5 V
So alternative (C) is the correct choice.