What is a primary use of dial indicators in mechanical setups?

Dial indicators are precision instruments predominantly utilized to assess mechanical runout, which refers to the deviation of a rotating component from its ideal circular path. In conditions where components like shafts or wheels may not be perfectly true, dial indicators provide an accurate means to quantify any wobbling or misalignment. This precise measurement is crucial in mechanical setups to ensure proper functioning, prevent excessive wear, and maintain equipment integrity.

The other functions listed are typically performed using different types of instruments. For example, measuring fluid levels often involves the use of level gauges or floats, angular displacement is usually determined with the help of protractors or angular gauges, and electrical resistance is measured with ohmmeters or multimeters. Thus, while each of these tools serves important roles in their respective measurements, dial indicators are specifically designed and most effective for evaluating mechanical runout.