If G1 = −80 μV and the output voltage is 20 μV, what is the voltage at G2?

To determine the voltage at G2 given that G1 = −80 μV and the output voltage is 20 μV, we can utilize the relationship between the input and output voltages in a differential measurement system, such as those commonly used in sleep studies.

In a differential system, the output voltage is essentially the difference between the voltages at the two input terminals (G1 and G2). The relationship can be expressed mathematically as:

Output Voltage = G2 - G1

Rearranging this formula to solve for G2 gives us:

G2 = Output Voltage + G1

Substituting the given values into this equation:

G2 = 20 μV + (−80 μV)

This simplifies to:

G2 = 20 μV - 80 μV = −60 μV

Therefore, the voltage at G2 is calculated to be −60 μV. The selection that reflects this calculation is the option indicating that G2 is −60 μV.

In the context of the choices available, the understanding of how to derive G2 from the output voltage and G1 reinforces the importance of grasping differential voltage measurement principles, particularly in the analysis of electrical signals in sleep studies.