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Bolts of uniform strength: verify the method involving drilling through the head. Statement: To obtain a bolt of uniform strength, an axial hole is drilled through the head down to near the threaded portion so that the shank’s net area equals the thread root area (making stress uniform). Choose the correct option (True/False).

Difficulty: Easy

True
False
True only for coarse threads
False; the shank should be made thicker, not drilled

Correct Answer: True

Explanation:

Concept
A bolt of uniform strength is designed so the minimum cross-sectional area occurs uniformly along the length, avoiding stress concentration at the threaded root. One recognized method is to drill an axial hole in the head/shank so that the effective shank area ≈ thread root area.

Alternative method
Reducing the shank diameter to the root diameter is another common approach.

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