9. The maximum voltage gain of an op-amp is 100,000. The voltage gain at the cut-off frequency is:
a) None are correct
b) 97 dB
c) 50 dB
d) 100 dB
a) None are correct - The maximum voltage gain of an op-amp is a measure of its open-loop gain, which is the gain when no feedback is applied. The cut-off frequency refers to the frequency at which the gain of the op-amp begins to decrease. However, the question does not provide any information about the specific cut-off frequency being referred to, so it is not possible to calculate the voltage gain at that frequency.
The voltage gain at the cut-off frequency of an op-amp can be calculated using the formula:
Voltage gain(dB) = 20 log10(Av)
Where Av is the voltage gain.
Given that the maximum voltage gain of the op-amp is 100,000, we can calculate the voltage gain at the cut-off frequency by substituting the value into the formula:
Voltage gain(dB) = 20 log10(100,000)
= 20 * 5
= 100 dB
Therefore, the correct answer is d) 100 dB.