Which measuring tool is specifically designed for measuring the diameter of holes?

• A. Caliper
• B. Vernier scale
• C. Dial bore gauge
• D. Micrometer

Answer: (C)

The dial bore gauge is specifically designed for measuring the diameter of holes. It features a long, thin probe that can easily be inserted into a hole to gauge its diameter accurately. The gauge utilizes a dial that indicates the measurement, allowing for precise readings of internal diameters, especially in applications where conventional measuring tools may not fit.

This tool is particularly useful in situations where the hole's diameter needs to be measured at various depths or in tight spaces where traditional calipers or micrometers might not be effective. Being designed for this specific purpose, the dial bore gauge provides an efficient and reliable way to check the dimensional integrity of holes, vital in many machining and manufacturing processes.