Question

The length of the metal end of a plain stud of diameter 30 mm is

• A. 10 mm
• B. 24 mm
• C. 30 mm
• D. 66 mm

Hint:

Use the standard formula: Metal end length = 2.2 × diameter (d)

Answer 1

The Correct Option is D

The metal end length of a stud is typically calculated as 2.2 times the nominal diameter.
This is a standard proportion used for engineering design of fasteners.
Given: Diameter = 30 mm
Required end length = \( 2.2 \times 30 = 66 \text{ mm} \)
Thus, the correct length of the metal end is 66 mm.
Other options like 10 mm or 24 mm are far too short for proper thread engagement, and 30 mm just equals the diameter, not sufficient for full grip.