Final answer:
To balance a Wheatstone bridge with the given values, R3 must be adjusted to 350 ohms. This is calculated using the ratio R1/R2 = Rx/R3 and the provided resistance values.
Step-by-step explanation:
To balance a Wheatstone bridge, the resistance R3 must be adjusted so that the ratio of R1 to R2 is equal to the ratio of Rx to R3. Given the values R1 = 50.0 ohms, R2 = 175 ohms, and Rx = 100 ohms, we can use the Wheatstone bridge balance condition which states that R1/R2 = Rx/R3. Using this relationship, we find the unknown resistance R3 by rearranging the formula to solve for R3, giving us R3 = (Rx × R2) / R1.
R3 = (100 ohms × 175 ohms) / 50.0 ohms
R3 = 17500 ohms / 50.0 ohms = 350 ohms
Therefore, the resistance R3 needs to be adjusted to 350 ohms to balance a Wheatstone bridge.