A screw having coefficient of friction equal to or greater than the tangent of the load angle is known as
- A. Machine screw
- B. Self locking screw
- C. Set-screw
- D. Ball-bearing type screws
Answer: B. Self locking screw
Explanation: Condition for self-locking: $\phi \ge \alpha$ or $\tan \phi \ge \tan \alpha$, where $\mu = \tan \phi$.